Boosting Brand Citizenship Behavior through Internal Green Marketing: The Role of Brand Trust and Willingness to be Environmentally Friendly

Green marketing is a critical issue in today’s society. The purpose of this study is to investigate the influence of internal green marketing (IGM) on brand citizenship behavior (BCB). Drawing on the theoretical foundations of social identity theory, cognitive consistency theory, and social exchange theory, this study presents and validates a unique model that examines the mediating effect of brand trust and the moderating effect of willingness to be environmentally friendly on the relationship between IGM and BCB. Using a sample of 176 employees employed in a telecommunication company in Jordan, the findings of this study revealed that internal green marketing is a strong predictor of BCB. Further, the positive effect of internal green marketing on brand citizenship behavior is mediated by brand trust. The findings of this study also confirmed the contingent role of willingness to be environmentally friendly on the relationship between IGM and BCB. Theoretical and managerial implications have been provided accordingly.


Introduction
The world has been very alarmed and concerned about the environmental issues that affect all humankind. A growing number of companies are struggling to enhance their environmental positions by promoting their environmental initiatives in public Szabo and Webster (2021). Environmental issues have become one of the critical issues for managers in the recent decade due to the growing concern about the sustainability of the natural environment (Keszey, 2020). This concern has increased dramatically in recent years despite universal technological development and entering the third millennium. Complex environmental issues have appeared such as global climate change, the consumption of environmental fortune, air defilement, and increased greenhouse pollution, which has a dramatic effect on ecosystems, industry waste, shrinking forest area, and increasing desertification.
Over the last few decades, growing numbers of research started focusing on environmental marketing (e.g., Szabo and Webster (2021). For instance, the study of Pham et al. (2018) argued that a firm's environmental marketing strategy plays a significant role in enhancing organizational behavior and boosting employee commitment and trust. Despite the significant importance of environmental marketing, the majority of studies on the subject neglect the impact of internal green marketing (IGM) initiatives in increasing voluntary employee support for the brand. The idea of voluntary employee behavior that promotes and supports the brand is known as brand citizenship behavior (BCB) (Xie et al., 2014). Despite the importance of the BCB concept, studies about BCB are scarce and are still a developing research area (Xie et al., 2014). By taking into concentration the growing importance of environmental initiatives of companies, this study aims to enrich the broader domain of environmental initiatives by investigating the following research questions: What is the effect of IGM on BCB? How does IGM affect BCB? Is the relationship between IGM and BCB contingent on the employee's willingness to be environmentally friendly?
The remainder of this study is as follows. First, the relevant theoretical background of the study's constructs and develop the hypothesis are presented. This is followed by a description of the methodology and data collection procedures used in this study. Next, the result and a theoretical and managerial discussion are provided. The study concludes with some limitations and directions for future studies.

Theoretical background and hypothesis development
Environmental protection is one of the most significant concerns to the universe (Almodarresi et al., 2019). Green marketing is a differentiated activity that a company is involved in those aims to increase the well-being of the societies as well as the company's identity (Mi et al., 2020). Consumers who care about the environment tend to use more environmentally friendly products (Almodarresi et al., 2019). Internal green marketing (IGM) is defined as a series of activities taking place within an organization that aims to pollinate environmental values across the organization to embed a wider corporate green culture (Papadas & Avlonitis, 2014). Such activities include considering the environmental initiatives of employees into recruitment and promoting procedures, encouraging the use of eco-friendly products/services among workers, and promoting environmental awareness among workers Papadas et al. (2019). From a local perspective, it is clear that Jordan's awareness of environmental problems is growing, which has led to significant improvement in the environmental commitment of governmental and nongovernmental agencies. This led companies and consumers in Jordan to the spread of awareness, the issuance of laws to support the green policies and to ensure compliance with global environmental standards (Alsmadi, 2007).
Brand citizenship behavior (BCB) refers to the voluntary behavior that benefits the corporate brand (Morhart et al., 2009). The study of Nyadzayo et al. (2015) defined BCB as the internal employees' voluntary activities on generic behavior that contribute to the viability and vitality of the brand. According to Piehler (2018), when employees have a high level of BCB, they will be more likely to comply with brand-related policies, engage in extra-role behaviors (e.g., recommending the brand to other stakeholders), defend the brand, and develop ideas and participate in training as well as make suggestions to improve the output of the organization.
BCB is operationalized in different ways. For instance, the study of Burmann et al. (2009) and Xie et al. (2014) argued the main three dimensions of BCB: the willingness for further development, willingness to help, and brand enthusiasm. Similarly, the study of Nyadzayo et al. (2015) comprised BCB into brand endorsement, helping behavior, and brand enthusiasm. Based on social identity theory (Tajfel, 1974), individuals tend to associate themselves with companies that involve enduring, differentiated activities that aim to enhance a customer's self-esteem (Bhattacharya & Sen, 2004). An individual's identification with a company leads to a psychological attachment of the individual with the company, which motivates the individual to commit to achieving the company's goals and engage in voluntary initiatives on its behalf (Bhattacharya & Sen, 2003). Increasing the level of identification would increase the level of the attachment of an employee with the company (Bhattacharya & Sen, 2003), which in turn will induce BCB due to the feeling of personal obligation to the brand as a group (Burmann & Zeplin, 2005). Moreover, the findings of Javid et al. (2016) showed that internal brand marketing is positively related to the brand's citizenship behavior. Therefore, the following hypothesis is proposed: H1. Internal green marketing has a positive impact on brand citizenship behavior Trust is considered one of the key factors in enhancing the relationship between the consumer and a certain brand (Vlachos et al., 2009). Brand trust has been defined as the psychological state that exists when an individual, e.g., an employee, has confidence in the integrity and reliability of an exchange partner, e.g., an organization (Kimpakorn & Tocquer, 2010). It has been considered as a critical factor in the success of the relationship between employees and the company (Lewicki & Bunker, 1996). In this study, we argue that brand trust plays a significant role in assimilating and exploiting a company's IGM and converting it to brand citizenship behavior (BCB). When the employees have brand trust, they will demonstrate a high level of BCB, which is based on the motivation that drives individuals to justice (John & Carrell, 1979). Kim et al. (2015) claimed that companies are presently looking for acquiring customer faith and trust just like a method to build bonds.
On one hand, we consider that brand trust is one of the consequences of IGM. In this vein, trust has been considered as one of the types of identification that is resulted from corporate involvement in pro-social behavior (Aljarah, 2020). On the other hand, we argue that brand trust is an antecedent of BCB. To develop a high level of BCB, firms need to change employee perceptions of the firm's brand (Xie et al., 2014). Drawing on the cognitive consistency theory (Heider, 1946), individuals strive to maintain psychological harmony among their beliefs, attitudes, and behaviors when they perceive conflicting tensions. If employees recognize the trustworthiness of a company, they are more likely to exhibit voluntary behaviors, e.g., BCB, conforming to their existing beliefs and attitudes. Empirical evidence seems to support this argument. Erkmen and Hancer (2015) indicated that brand trust contributes to employee BCB. Vlachos et al. (2009) claimed that trust has a mediating role in corporate social responsibility evaluation and seems to be an important subprocess regulating the effect of individual attributions on patronage and recommendation intentions. Chen and Chen (2010) claimed that brand trust influencing the consumers' decision, and they conducted a positive relationship between brand trust and consumer confidence as a result. Moreover, Kim et al. (2018) explained in their research that trust in a brand makes a better brand and customer bonds, which must be constantly ensured to participate in brand loyalty. Thus, brand trust can reinforce BCB. Based on this, the following hypotheses are proposed: H2. Internal green marketing has a positive impact on brand trust H3. Brand trust has a positive impact on brand citizenship behavior H4. The positive relationship between internal green marketing and brand citizenship behavior is mediated by brand trust Previous studies have investigated whether employees' ecoinitiatives behavior, i.e., employees' willingness to be environmentally friendly, has interactive effects with corporate environmental policies, e.g., IGM, on the individual behaviors like BCB (Paillé & Raineri, 2015). However, researchers agree regarding the considerable and significance of these effects. Kim et al. (2019) found that when a firm has good corporate environment abilities, employees' eco-friendly behavior significantly affects the employees' commitment and attitudes. Environmentally friendly consumers expect to obtain positive feelings and satisfaction from these practices, and this means they will show greater readiness towards the green brand, unlike consumers who are not using the green brand (Abdul-Muhmin, 2007). Chaudhary (2020) claimed that employees' personal environmental values have no significant moderating effect on the relationship between green management practices and employees' green performance behaviors. Meanwhile, Alhadid and Abu-Rumman (2014) found that environmental behaviors of human resources within an organization moderate the relationship between green innovation and organizational performance.
Social exchange theory (SET) (Blau, 1964) supports the link between employee attitudinal evaluations and employee citizenship behavior. SET explains that the relationship between employees and an organization is seen as social exchanges, in which employees reciprocate the positive behaviors of an organization towards the internal and external environment (Lii & Lee, 2012). As such, when a company engages in environmental programs, employees may perceive that company to be altruistic, which could lead to more favorable attitudinal evaluations of the same company (Nan & Heo, 2007). Hence, people, e.g., employees, are more likely to engage in reciprocation that may benefit that company (Groth, 2005). BCB may be one type of benefit.
Providing employees with high levels of environmentally friendly policies has positive effects on their behaviors and attitudes (Kim et al., 2016). We posit that firms with high levels of employee willingness to be environmentally friendly will generate strengthened effects on BCB. Employees are more likely to engage in BCB when evaluating a firm using corporate social responsibility (CSR) altruism towards the internal and external environment, suggesting that high IGM may compensate employees for these CSR attributions. Conversely, we predict that firms with low levels of employee willingness to be environmentally friendly will generate weak effects on BCB. Employees are less likely to engage in BCB when evaluating a firm using low levels of IGM attributions, suggesting that low levels of IGM may increase employee scepticism towards these exploitative CSR initiatives. In other words, employees are not being compensated for bad purposes behind CSR motivations, which in turn decreases employees' trust, recommendation intentions, and BCB. Provided that, the following hypothesis is proposed: H5. The positive relationship between internal green marketing and brand citizenship behavior is mod erated by the willingness to be environmentally friendly The research conceptual model is illustrated in Figure 1.

Sampling and data collection
This research concentrates on the telecommunication sector in Jordan. The telecommunication sector in Jordan has markedly developed in the past years and is taken as the foremost competitive marketplace within the Arab region, as stated by the Competition Intensity Index (2014) discharged via Arab Advisors Group (Obeidat et al., 2015). The sample of individuals surveyed was selected from the telecommunication sector in Amman, Jordan, and employees who work in an organization located in the capital city of Amman. This study selected "Orange Company," a well-known company engaged in an eco-friendly activity that also represents one of the most important telecommunication companies in the country. Using the convenience sampling method, we selected the largest Orange Company branch by sales volume in Amman, Jordan. We distributed 430 questionnaires. The participants were first asked about their IGM, brand trust, willingness to be environmentally friendly, and the brand citizenship behavior (BCB) of Orange Company. Then, they were asked to answer demographic questions, including gender, age, education, job level, monthly income, and work experience. We received 250 questionnaires in response. After removing those that were invalid due to missing data and unengaged responses, 176 complete and valid questionnaires were obtained.

Measurements
A well-developed questionnaire was used to collect data. A fivepoint Likert scale (1: strongly disagree to 5: strongly agree) was used. IGM was measured with 7 items adopted from Papadas et al. (2017). BCB was measured by adopting a seven-item scale from the study of Chiang et al. (2012). Brand trust was measured by adopting a three-item scale from the study of Sohail (2017). Willingness to be environmentally friendly was measured by adopting a four-item scale from the study of Kautish et al. (2019).

Demographic description of participants
The demographic profiles of participants are reported in Table  1. Table 1 indicates that females represent 46.6% of the sample, and males make up 53.4%. Regarding the education level, the majority of the respondents were well-educated, as 46.0% possess a bachelor's degree, 6.3% have a postgraduate degree, and 43.8% have a diploma-college degree. From these percentages, we can conclude that most managerial positions are occupied by graduated individuals. Regarding job level, employee and owner/executive level had the same percentage, 31.8%, senior or middle management had 31.3%, and intermediate or entry-level had 5.1%. The respondents' ages for 18 or less is 1.7% only, between 21-39 is 55.1%, between 40-59 is 40.9%, and 60 and above is 2.3%. Regarding salary, 4.5% of respondents earn a salary of less than 300 Jordanian Dinar (JD), 50.6% have a salary between 300-800 JD, and 44.9% have a salary of more than 800 JD. As for the work experience, 56.8% of the individuals have more than three years of experience, 8.5% have fewer than one year, and 34.7% have 1-3 years of experience.

The validity and reliability analyses
Cronbach's alpha has been used to examine the reliability of the constructs. As shown in Table 2, the value of Cronbach's alpha ranged between 71 (brand trust) and 89 (IGM), which, in turn, ensured the reliability of the construct of the study (Nunnally, 1978). Confirmatory factor analysis was conducted to test the construct's validity use within the current sample. The proposed research model fit obtained data well (x 2 /df = 2.93 < 3.00; GFI = .93 > .90; CFI =.97 > .90; NFI = .95 > .90; RMSEA = .07 < .08), yielding in a defended goodness-of-fit. Moreover, the factor loading was to the items was more than 0.65, the composite reliabilities (CRs) for each construct were higher than 0.70, and the normal distinction extricated (AVE) for all variances was more than 0.50, Thus, the instrument and contingent validity for each construct were guaranteed (Fornell & Larcker, 1981).

Hypotheses testing
A linear regression analysis has been conducted to examine the direct relationship. As shown in Table 3, IGM was a strong predictor of brand citizenship behavior (BCB) (β = 0.67; p < 0.05). Thus, H1 is strongly supported. This means that the more engagement in IGM initiatives the more BCB will be generated. The same table illuminates that IGM had a statistically significant effect on brand trust (β = 0.81; p < 0.05). Thus, H2 is strongly supported. Further, brand trust was a strong predictor of BCB (β = 0.60; p < 0.05). Hence, H4 is supported. Hypotheses 3 has been examined using PROCESS (Version 3.5), developed by Hayes (2013). The 95% bias-corrected bootstrapped confidence interval (N = 5000) was generated (Preacher et al., 2007   Note: *** = p < 0.001; WTE= willingness to be environmentally friendly trust reported for a slightly lower significant effect (β= .33, 95% bias-corrected CI [0.23, 0.45]). This signifies the mediation effect of brand trust in the relationship between IGM and BCB. Thus, H4 is supported. Moreover, the interaction effect of willingness to be environmentally friendly with IGM on BCB was reported for a significant effect. Hence, H5 is supported.

Discussion
This research aims to investigate the effect of IGM on brand citizenship behavior (BCB) on the employees of the telecommunication sector/case study on Orange/Jordan. This study is based on a quantitative approach technique to gather the primary data. The researchers developed a questionnaire to measure the study constructs, which included 27 items. The findings of this study revealed that IGM plays a significant role in generating BCB. Further, IGM has a strong predictor of brand trust, which in turn, has a significant predictor on BCB. The result of the mediation analysis confirmed the mediation role of brand trust on the relationship between IGM and BCB. While the result of the interaction effect revealed a significant positive effect of willingness to be environment friendly on the relationship between IGM and BCB.
The findings of this study contribute to the literature in several ways. This study contributes to the understanding of employees' pro-environmental behavior by investigating the moderating effect of employees' willingness to be environmentally friendly on the relationship between IGM and BCB. The findings of this study reveal that the willingness of employees to be environmentally friendly serves as a boundary condition of the consequences of IGM on employees' subsequent behavior. For the employee who has a high willingness to be environmentally friendly, IGM can strongly trigger their positive response toward their work and boost their BCB. However, this relationship between IGM and BCB does not work effectively when the employee has a low level of willingness to be environmentally friendly. In parallel with previous studies (Alhadid & Abu-Rumman, 2014;Chaudhary, 2020;Kim et al., 2019), this finding provides converging evidence that an individual's willingness to be environmentally friendly play a critical role in the success of a firm's environmental initiatives on individual responses. Yet, the findings of this study extend the findings of previous studies by incorporating it as a moderating variable between IGM and BCB. Further, these findings contribute to the literature for the first time, to the best of the author's knowledge, investigating BCB as one of the core consequences of IGM. Several studies have investigated the antecedents of BCB (Burmann et al., 2009;Piehler et al., 2019). However, the majority of previous studies neglect the effect of IGM as one of the key antecedents of BCB. Our study contributed to the literature by utilizing the effect of IGM in enhancing BCB. Moreover, the findings of this study contributed to the literature by investigating the mechanism of how IGM affects BCB through adding brand trust as a mediator variable. The findings of this study revealed that brand trust is one of the essential factors that should be considered for the efficacy of IGM on BCB. When employees of an organization perceive the IGM initiatives of the company, they trust more in the company, which, in turn, encourages them to engage more in voluntary behaviors such as BCB. The finding contributes to the literature as it is the first study to try to understand the relationship between IGM and BCB from the perspective of brand trust.

Managerial contributions
The findings of this research have several implications for managers and marketers, especially in the service and telecommunication sectors. The practical implementation of this study highlights the importance of IGM to the telecommunication industries, particularly the ones operating in Jordan. The local telecommunication sector faces many challenges to stand out from other global rivals, and, for these companies to survive, they must continually adjust to environmental changes and incorporate these changes in the long-term strategy of the firm. Managers and marketers should consider investing in IGM as the findings of this study support the positive relationships between IGM and employees' brand citizenship behaviors (BCB). Further, the companies strive to spread trust among their employees. By doing so, companies can get the most outcome from their IGM initiatives. Further, and based on the findings of this study, companies should be aware of the level of their employees' willingness to be environmentally friendly, as it plays a significant role in the effectiveness of IGM initiatives on employee behavior. To provide green solutions to the problems in a more inno-vative way from the employees. Companies should lead to obtaining greater internal green organizational communication (Chaudhary, 2020). Companies should start implementing green training courses similar to all employees, and this will make them appreciate green management and thusly implement strategic plans more smoothly and efficiently. Therefore, companies should regularly evaluate the green performance of employees and encourage such behaviors, which will lead to greater benefit and profit and will encourage participation and involvement in green initiatives.

Limitation and directions for future studies
Several limitations should be acknowledged. Firstly, the data was collected during the COVID-19 Pandemic, limiting access to greater data collection so the findings could have more statistical power. The findings of this study also did not consider the effect of demographics, e.g., gender, age, and education, in the proposed research conceptual model. This study additionally chose one green brand (Orange Company) to conduct the research. For future studies, the researchers may consider this demographic when examining the relationship among the construct of this study. Further, because the convenience sampling method that this study has applied may limit its generalizability, future studies are encouraged to implement different data collection methods when examining the relationship among the construct of the study. Moreover, since the target sample for the study was employees (brand citizenship behavior) and researchers chose one green brand on which to conduct the study, future scope researchers can do the study on more than one green brand to achieve inclusiveness. The findings of this study suggest that brand trust partially mediates the relationship between IGM and brand citizenship behavior. This means that other variables may be included as a mediator in the relationship between IGM and brand citizenship behavior, which could be a matter of future studies. Most previous green marketing studies were done in developed countries (Papadas et al., 2017), while few have been conducted in developing countries, especially in Jordan. Future studies could apply the conceptual model in different contexts and different countries.

Conclusion
In the present study, we investigate the influence of IGM on brand citizenship behavior (BCB) within a telecommunication company. Other essential factors, e.g., brand trust and willingness to be environmentally friendly, we're also combined with forming brand citizenship behavior into the proposed theoretical framework. In the service and telecommunication context, empirical research on IGM and its relationship to construct variables affecting brand citizenship behavior have been neglected in previous literature. The conceptual framework of the present research offers important insight on the impact of IGM on brand citizenship behavior, and the importance of brand trust as a mediator was identified. Additionally, the bond between IGM-BCB relationships was under the moderator influence of willingness to be environmentally friendly. The present study has taken a step further by joining IGM, brand trust, willingness to be environmentally friendly, and brand citizenship behavior into one conceptual framework in the service industry.