The Washington Post publisher Fred Ryan is stepping down after nine years atop the paper, he said in an email to staffers on Monday. His last day will be August 1.

“We have accomplished one of the most extraordinary transformations in modern media history,” Ryan wrote to staffers. “We have evolved from a primarily local print newspaper to become a global digital publication.”

Amazon founder and chairman Jeff Bezos, the Post’s owner, named Patty Stonesifer as interim CEO.

Ryan will chair the Ronald Reagan Presidential Foundation and Institute’s new nonpartisan venture: The Center on Public Civility, which will receive planning and design support from Bezos, Ryan said.

“I have a deep and growing concern about the decline in civility and respectful dialogue in our political process, on social media platforms and more broadly across our society,” the outgoing publisher wrote, later adding: “Today, the decline in civility has become a toxic and corrosive force that threatens our social interactions and weakens the underpinnings of our democracy. I feel a strong sense of urgency about this issue.”