Vanessa Feltz has announced she is leaving her two BBC radio programmes after more than two decades.
The broadcaster will exit her early breakfast show on BBC Radio 2, as well as the breakfast show she presents on BBC Radio London.
Feltz said she had "loved every moment" and would miss her "beloved" listeners and colleagues.
But, she said, she had to step down "to catch up on a much needed decade's deficit of beauty sleep".
Feltz has presented shows on BBC Radio London since 2001 and Radio 2 since 2011.
The 60-year-old will host her final early breakfast show on BBC Radio 2 on Friday.
After a two-week break, she will then cover Jeremy Vine's show for a fortnight as planned, from 15 August.
Her last day of covering Vine, on 26 August, will be her final day at BBC Radio 2, and also mark her final BBC Radio London show.
Radio 2 controller Helen Thomas said she wanted to "thank [Feltz] wholeheartedly for the thousands of middle-of-the-night starts she's made to entertain the Radio 2 listeners"
Feltz became emotional as she addressed listeners on both networks on Thursday morning.
"I knew I was going to cry," she said on Radio 2. "I have been honoured to share the small hours with you."
"I'm absolutely heartbroken to be leaving as I know you can tell, and I will miss you every day with all my heart."
Speaking a few hours later on BBC Radio London, Feltz said through tears: "Lovely listener, we are woven into the DNA of one another's lives in a very special way."
While Feltz's Radio 2 show features music, her BBC Radio London show is speech-based, with news items and calls from listeners.
"Although I'm leaving the show, I'll continue to expect hugs from my lovely listeners when I see them on the streets of London!" she said,
The broadcaster added she was looking forward to being able to sleep for longer in the mornings after her two shows come to an end.
"I will enjoy a dollop of energy-boosting shut-eye to swing from zip-lines with my three effervescent grandchildren and frolic with my fiancé Ben, who irritatingly remains 10 years younger than me!" she said.
Feltz is one of the highest-paid radio presenters at the BBC, earning more than £400,000 for hosting her two daily radio shows.
It has not yet been announced who will replace her, but the BBC said schedule announcements would follow in due course.
Speaking on the Radio 2 breakfast show after Feltz announced her departure, Zoe Ball described her fellow presenter as "always glamorous and quite possibly the cleverest person I know".
Ball said: "I'm not going to lie, we are all in tears at Radio 2. She's always been outrageous and the hardest-working lass.
"Wherever she goes next, whatever she does, she will be golden at it and they'll be very lucky to have her. We will give her the bumps at some point."
Another Radio 2 DJ, Steve Wright, announced earlier this month he was leaving his weekday afternoon show.
Chris Burns, the controller of local audio commissioning, said: "Every weekday Vanessa has breezed straight from her Radio 2 programme into the Radio London breakfast show, barely pausing for breath.
"She has effortlessly entertained her 'lovely listener' and sternly held the city's and country's decision makers to account."
Feltz began presenting Radio 2's early breakfast show in January 2011, from 5am-6.30am, which was extended to 4am in January 2021.
Before taking over the BBC Radio London breakfast show in January 2016, Feltz presented the mid-morning show on the station, and the mid-afternoon slot prior to that.
Feltz also regularly appears on ITV's This Morning, writes a newspaper column in the Daily Express and has previously taken part in Celebrity Big Brother and Strictly Come Dancing.