The first African-American member of Twitter’s board of directors — Debra Lee is stepping down from her position after three years of services at the micro-blogging platform. Also Read - Twitter Announces New Feature That Would Let Users Charge Followers, Netizens React

The exact reasons for Lee’s departure from Twitter remain undisclosed as of now. Also Read - Bhim Army Chief, 5 Indian-Origin Persons on TIME's List of 100 Emerging Leaders

However, after Twitter, Lee would now be part of the board of directors at US-based telecom major AT&T. Also Read - Btrust: With Focus on India And Africa, Twitter CEO Jack Dorsey, Jay-Z Announce Bitcoin Endowment

“I believe Twitter has a bright future, and I wish Jack (Dorsey) and the entire company continued success,” CNET quoted Lee as saying on Monday.

Twitter, like other tech companies, has been under criticism for not having enough diversity on its board of directors.

When Lee joined Twitter’s board in 2016, civil rights activists praised Twitter’s decision.

Prior to joining Twitter, Lee served as the Chairman and Chief Executive Officer (CEO) of BET — the parent company for Black Entertainment Television.