Vernon Kay and Reggie Yates to leave Radio 1

"When I was offered a contract extension I thought long and hard," said Kay, "but after 12 years of working weekends, I felt it was the right time to leave as the girls are now both in school so weekends are more precious than ever."

"I have absolutely loved my time hosting the Chart Show," added Yates. "It's been a privilege to deliver to the nation the weekly No.1 song, but after 10 years at Radio1/1Xtra I am looking forward to focusing on other projects and new challenges."

After joining the station earlier this year, Radio 1's Request show host Jameela Jamil will takeover Yates' Chart Show slot, becoming the first solo female presenter of the show since it began in the 1960s as Pick Of The Pops.

"I am absolutely delighted and honoured," revealed Jamil. "I'm fully aware that I have big shoes to fill and am so excited to get started... I cannot thank Radio 1 enough for the amazing opportunity."

In addition, Matt Edmonson - who currently presents a Wednesday night comedy show on Radio 1 - will fill Vernon's shoes with a new weekend morning show from 10am-1pm, as well as covering Sara Cox's Sunday morning show while she presents Fearne Cotton's 10am-1pm weekly broadcast during her maternity leave. Edmonson's show has been billed as "packed full of music and cheeky, irreverent humour".

Talking about his new show, Edmonson said: "I am delighted that from January I'll be spending my weekends sandwiched between Gemma Cairney and Huw Stephens - it is literally a dream come true, although of course in my actual dream everyone was wearing fewer clothes."

YouTube sensations Dan and Phil - who have collectively amassed 100 million views and almost one million subscribers with their respective YouTube channels, Danisnotonfire and AmazingPhil - will take over the reigns of the Sunday night Radio 1 Request show between 7-9pm. The pair have previously presented shows for the station, including a Christmas special, and in their new format will be interacting with listeners and playing the music they want to hear.

According to Dan and Phil, "We are extremely excited to start this new show! It's going to be an explosive two hours of great music, lols and interactive content that's completely visualised on the Radio 1 website and we want it to stand out as one of the highlights of the week!"

And finally, comedian Tom Deacon will take over Matt Edmonson's current Wednesday night comedy show at 9pm each week. "I've been doing stand-up comedy for six years and presenting on Radio 1 for the last three," said Deacon, "so I'm delighted to be bringing these things together. Expect awesome comedians live in the studio, great music, and lots of laughs..."

Controller of BBC Radio 1 and Radio 1Xtra, Ben Cooper, added his thoughts on the presenting overhaul: "I'd like to thank Vernon and Reggie who have both been excellent ambassadors for Radio 1 and Radio 1Xtra during their ten years with us. I wish them all the very best.

"I'm excited by our brand new shows, which will appeal to the smartphone generation with our audience able to listen, watch and share Radio 1's great content."

The changes fall into step with the recent re-focus of the station towards a younger audience, famously put into effect with the replacement of long-running Radio 1 Breakfast Show host Chris Moyles with 28-year-old Nick Grimshaw earlier this year.

The new schedule changes will come into effect at the beginning of January.