DJ Sara Cox will replace Scott Mills as the host of Radio 2's breakfast show, the BBC has announced.
Cox, who is originally from Bolton, currently presents the station's teatime slot, which she has fronted since 2019.
The 51-year-old said she was "ecstatic, honoured and incredibly chuffed" to be taking over the station's flagship show.
"It's been a dream to host the breakfast show since I joined Radio 2 and it feels like a bit of a full circle for me," she added.
Cox will take over the breakfast show in the summer. The BBC said it would announce the new host of the teatime slot at a later date.
Opening her show on Thursday after the news was announced, Cox said: "It takes quite a lot to make me speechless, but when I got asked to host the Radio 2 breakfast show I was momentarily lost for words."
Cox said it had been an "absolute blast" hosting teatime, describing her tenure as a "golden seven years", but added she was "absolutely buzzing" to be taking over breakfast.
"It's always been my dream," she said. "My energy has always been 'waiting-in-the-wings gal', but I'm so glad it's happening now, because I would not swap the last seven years of teatime for anything."
Gary Davies, who regularly covers daytime programmes when the main presenters are off, has been hosting Radio 2's breakfast show since Mills was sacked by the BBC in late March.
Mills was dropped after the corporation received new information relating to a police investigation over alleged historic sexual offences.
Hosting the Radio 2 breakfast show is one of the most high-profile and prestigious jobs in British radio, although it is not the station's most listened to programme.
The mid-morning slot, currently hosted by Vernon Kay, has been the most popular radio programme in the UK since 2019, a record it first achieved under Kay's predecessor Ken Bruce.
Before taking over the teatime slot from Simon Mayo in 2019, Cox presented other shows on the station including Sounds of the 80s and the weekday late-night programme.
She was also a regular stand-in on Radio 2's breakfast show during Chris Evans's tenure, and previously hosted the Radio 1 breakfast show in the early 2000s.
Cox has also presented several TV programmes for the BBC, including The Great Pottery Throw Down and book review series Between The Covers.
Last year, she raised £11.5 million for Children in Need by running the length of five marathons over five days.
Cox will become the station's second female breakfast host, after Zoe Ball. The show's longest-serving incumbent was Sir Terry Wogan, who presented it for more than 28 years in total.
A former model, Cox launched her broadcasting career in the late 1990s, presenting on MTV as well as Channel 4 shows The Girlie Show and The Big Breakfast.
Radio 2 chief Helen Thomas said she was "delighted" that Cox was taking over the breakfast show, saying that she "thoroughly deserves this gig".
"Sara is adored by her millions of listeners at teatime, and having regularly deputised in the slot, I already know she'll build a brilliant rapport with the breakfast audience and get the nation going each morning with her trademark warmth and humour," she said.
Mills was investigated by police between 2016 and 2019 after an allegation was made against him of a historic sexual offence involving a boy under the age of 16.
The offences were alleged to have taken place between 1997 and 2000, when Mills would have been in his mid-20s.
The investigation, which Mills said he fully co-operated with, did not lead to any criminal charges, after the Crown Prosecution Service determined there was insufficient evidence.
The BBC said it was made aware in 2017 of the investigation, but that new information had come to light in recent weeks that led to the DJ's dismissal on 27 March.
Mills released a statement acknowledging his dismissal and saying he fully co-operated with the police investigation.
However, he did not address the substance of the allegations, provide any further detail about them or offer a denial.
The 53-year-old said: "Since the investigation related to an allegation that dates back nearly 30 years and the police investigation was closed seven years ago, I hope that the public and the media will understand and respect my wish not to make any further public comment on this matter."
