The Guardian's head of news, Stuart Millar, is leaving the newspaper after 19 years.
Staff were told yesterday of Millar's departure in an email sent by new editor-in-chief Katharine Viner.
She said: "I'm writing to let you know that after a long career at the Guardian, Stuart Millar has decided it's time to move on.
"Over 19 years he has been a terrific colleague in news, working on big stories including Wikileaks and Snowden as well as the launch of Guardian US.
"We wish him all the best with what he does next."
Millar said in an email to staff: "Just wanted to say how grateful I am for having had such a brilliant time at the Guardian. It's the only place I've ever worked, from being a Scott Trust student at City through to head of news 19 years later.
"It has been an honour to work with such a world-class team of reporters and editors on some of the biggest stories around, and I look forward to watching you all take the organisation on to even greater success.
"So I leave with some trepidation about the outside world and I'm obviously very sad to go. But this felt like the right time to move on and I'm excited about the next challenge."
Millar took up his current role at The Guardian last summer.
Previously, he was deputy to Janine Gibson when she edited the title in the United States. He moved back to the UK at the same time as Gibson, when she was made deputy editor and editor of The Guardian's website.
Gibson, who missed out to Viner in the race to replace Alan Rusbridger as editor-in-chief, is to start as editor-in-chief of Buzzfeed in the UK in September.
Millar was previously news editor of The Guardian, the title's website and is also a former special projects editor.
He has not revealed his next job move and his Twitter profile currently says: "Resting."