Twitter founder and CEO Jack Dorsey is stepping down as the company’s leader.  

In a news release, Twitter said Dorsey would be replaced by Parag Agrawal, who has been the company’s chief technology officer since 2017. The move is effective immediately.  

“I’ve decided to leave Twitter because I believe the company is ready to move on from its founders. My trust in Parag as Twitter’s CEO is deep. His work over the past 10 years has been transformational. I’m deeply grateful for his skill, heart, and soul. It’s his time to lead,” Dorsey said in a statement.

Dorsey made his resignation official in a tweet Monday and attached a letter with an explanation of why he was leaving.  

“not sure anyone has heard but, I resigned from Twitter,” he wrote.

On Sunday, Dorsey tweeted “I love twitter.”

Dorsey, 45, founded the microblogging platform in 2006 and was CEO until 2008 when he was pushed aside only to return to the top spot in 2015.  

Last year, Elliott Management, a major stakeholder in the company, wanted Dorsey to choose between being CEO of Twitter or CEO of Square, a digital payment company he founded.  

Twitter’s stock rose on the news, but trading of the shares was suspended.

Some information in this report came from Reuters.