Jeff Bezos said Tuesday that he will step down as chief executive of Amazon, leaving the helm of the company he founded 27 years ago.

Bezos will transition to the role of executive chair in the third quarter of this year, which starts July 1, the company said. Andy Jassy, the chief executive of Amazon Web Services, will take over as CEO of Amazon.

Bezos has been Amazon’s CEO since its founding in 1995. He oversaw its growth from an online bookseller into a $1.7 trillion global retail and logistics behemoth, which has also made Bezos into one of the world’s richest people. Jassy has worked for Amazon since 1997 and currently serves as CEO of the company’s cloud business, Amazon Web Services, its biggest profit driver.

“This journey began some 27 years ago. Amazon was only an idea, and it had no name,” Bezos wrote letter to employees Tuesday. “The question I was asked most frequently at that time was, ‘What’s the internet?’ … Today, we employ 1.3 million talented, dedicated people, serve hundreds of millions of customers and businesses, and are widely recognized as one of the most successful companies in the world.”

“I will reiterate [Jeff Bezos] is not leaving,” Brian Olsavsky, chief financial officer of Amazon, told investors on Tuesday. “He’s going to be executive chairman, super important role, super active in the Amazon success story.”

Bezos said in his Tuesday letter that he is excited for the transition, which will free up more time for him to work on outside projects. As executive chair of Amazon, he will focus on “new products and early initiatives,” he said.

“Being the CEO of Amazon is a deep responsibility, and it’s consuming,” Bezos wrote. “When you have a responsibility like that, it’s hard to put attention on anything else. As Exec Chair I will stay engaged in important Amazon initiatives but also have the time and energy I need to focus on the Day 1 Fund, the Bezos Earth Fund, Blue Origin, The Washington Post, and my other passions. I’ve never had more energy, and this isn’t about retiring. I’m super passionate about the impact I think these organizations can have.”