Twitter co-founder Williams steps down from board

San Francisco: Twitter co-founder Evan Williams on Friday announced that he is stepping down from the board of directors of the the micro-blogging site at the end of the month.

"I'm very lucky to have served on the Twitter board for 12 years (ever since there was a board). It's been overwhelmingly interesting, educational-and, at times, challenging," Williams, who has served as the CEO of Twitter, tweeted on Friday.

While expressing his appreciation for almost 4,000 Twitter employees "who are doing the hard work every day," "I will continue rooting for the team as I focus my time on other projects," he added, reports Xinhua.

Williams succeeded Twitter founder Jack Dorsey to assume the role of CEO in 2008 until 2010, when he was replaced by Dick Costolo.

He is currently the CEO of Medium, a San Francisco-based online publishing tech company that was launched by himself in 2012.