Sir Terry Wogan confirmed to listeners today that he will step down from the BBC Radio 2 breakfast show at the end of this year and will be replaced by Chris Evans.

Wogan announced his departure on air, telling listeners it was the "hardest thing I have ever done in my broadcasting career".

But the 71-year-old DJ, who has presented the Radio 2 breakfast show in two stints for a total of 27 years, is not leaving Radio 2 altogether – he will present a new weekend show, launching early next year.

Evans, the former BBC Radio 1 breakfast host who joined Radio 2 in 2005, will present the Radio 2 breakfast show from January, going head to head with Radio 1's Chris Moyles. Evans had been widely tipped to inherit Wogan's flagship Radio 2 slot.

Wogan told listeners: "If the mail is anything to go by, most of the listening population have spotted a report that next year, I'm going to turn into Chris Evans. And I hate to tell you, but it's true.

"I was hoping to break it to you, my loyal listener, more gently. I wanted to be the first to tell you. It's the least I owe you, for endless years, countless hours of morning companionship, friendship, good humour, and laughter. Your loyalty and support has been a beacon of love in my life."

Evans said: "This is very much Terry's story, not mine, as well it should be. To step down from something you have done so well and for so long, and obviously still enjoy doing, must be a tough call even for such a stoic as Sir Tel.

"That said, although I will miss the drivetime show which I have loved for the last three-and-a-bit years, I couldn't be more excited at the prospect of hosting the flagship show on one of the BBC's national networks."

The Radio 2 breakfast show is the most popular in the country, with an average weekly audience of 7.93 million.

Wogan's first stint hosting the Radio 2 breakfast show lasted from 1972 to 1984, after which he left to present his three-times-a-week BBC1 chatshow, Wogan. He rejoined the station in 1993 for a second stint that was to last 16 years, establishing Wake Up To Wogan as the country's number one breakfast show.

One of the BBC's most familar faces, Wogan has presented the corporation's annual Children In Need appeal since 1978, when it began as a five-minute broadcast on Christmas Day. Children In Need became a live evening of programmes in 1980 and Wogan has hosted it ever since.

Wogan also presented BBC1's coverage of the Eurovision Song Contest from 1980 until last year.

If he is one of the BBC's best-known presenters, he is also one of the most outspoken. Last year he questioned whether BBC employees still thought they worked for one of the best broadcasters in the world and said corporation executives lacked the "old-fashioned thoroughness and commitment" of their predecessors.

He has also described Radio 1's Moyles as in "doubtful taste". The Radio 1 DJ responded by saying of Wogan that he would "tear that wig off his head and shove it up his arse".

Wogan also made headlines just last week when he described newsreading as a "piece of cake". In extracts released from his new book, the DJ said the job of newsreader was "not something to get self-important about... Before you start with the "fair play old boy, there's more to it than that!", I was a radio and TV newsreader and there isn't".

Evans joined Radio 2 in 2005 as host of its Saturday afternoon show before moving to the drivetime slot in 2006, replacing Johnnie Walker.

The switch by then controller Lesley Douglas proved controversial and generated hundreds of complaints from listeners.

But Evans's drivetime show won a Sony gold award for best entertainment programme in 2007 and 2009, two of five Sony gold awards won by Evans at Radio 2. The show currently has an audience of more than 5 million listeners.

Taking over from Wogan will be the fourth time Evans has presented a breakfast show on either TV or radio. He presented the Radio 1 breakfast show between 1995 and 1997, quitting after then controller Matthew Bannister refused his request to work four days a week.

He also presented the Big Breakfast on Channel 4 between 1992 and 1994 and was Virgin Radio breakfast DJ between 1997 and 2001.

Bob Shennan, Radio 2 controller, said Wogan's contribution to the success of Radio 2 over the last 16 years was "immeasurable".

"His unique talent has provided millions of listeners with the soundtrack to their morning. Terry is unequivocally the most accomplished radio presenter of his generation," Shennan added.

"I know his TOGs [Terry's Old Geezers and Gals] and TYGs [Terry's Young Geezers and Gals] would like me to thank Terry for his years of devotion to the programme and I'm delighted that Terry has agreed to present a new, exciting show on Radio 2 next year."

The BBC's director of audio and music, Tim Davie, said: "Terry is a legendary talent and I'd like to pay tribute, on behalf of the BBC and his millions of devoted listeners, to his unique place in UK broadcasting history.

"I'd like to thank Terry for entertaining his army of fans for many years and I'm delighted that he has agreed to continue to entertain the nation on Radio 2."

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