Kerry O'Brien steps down from The 7.30 Report (Source: Publicity image, ABC)

Kerry O'Brien will step down as editor and presenter of the ABC's nightly current affairs program, The 7.30 Report, after fifteen years at the helm.

In a statement to ABC staff this afternoon, O'Brien, 65, said he would exit the chair in December this year.

"Quite simply, it's time for a new chapter," he said.

"I've been in the pressure cooker of daily current affairs hosting and interviewing for twenty-one straight years including six years at Lateline, and it's becoming something of a marathon."

"It has been an absolute privilege to work with some of the most talented and dedicated professionals in the business, and I leave with confidence that The 7.30 Report will be at the heart of ABC News and Current Affairs coverage for years to come. This has been a great year for the program, and it’s good to leave on a high note."

In thanking his audience, the veteran journalist said, "I would also like to thank an extremely generous audience, including those who may have occasionally thrown a shoe at the screen."

O'Brien confirmed that he would "begin a new association with the ABC in the new year, but one that will allow me time to take a breath and consider what else I might want to do with the rest of my life."

The broadcaster's director of news, Kate Torney, said, "Kerry has consistently set the news agenda and this has never been more apparent than this year when he has delivered a number of game-changing interviews with industry and political leaders, including (US) president Barack Obama."

Meanwhile, ABC's managing director, Mark Scott, responded to the announcement via his twitter feed this afternoon:

"It’s true. Kerry O’Brien has announced he is retiring from The 7.30 Report at the end of the year," confirming he would "step into a new [reduced] role" next year.

"As the ABC approaches its eightieth year, few journalists have played such an important role, for such a long time, with such integrity and distinction, as Kerry O’Brien," Scott later said.

"On behalf of all of his colleagues, I want to thank Kerry for his tireless commitment to the best in ABC journalism through his leadership at The 7.30 Report."

The show will remain key to the broadcaster's evening line-up. A replacement has yet been named.

Media Spy discussion: Kerry O'Brien leaving The 7.30 Report