Sandi Toksvig is to leave The Great British Bake Off after three years.
The presenter said she wanted to focus on other work commitments. "As my waistline will testify, Bake Off is an all-consuming show," Toksvig tweeted
"Bake Off is a wonderful programme which has already proved it can happily withstand a change of hosting personnel," she added.
Her co-host Noel Fielding said he would miss her, but knew "we were lucky to have her for 3 amazing years".
The pair took over presenting duties when the programme in 2017.
Prior to that, the show aired on the BBC and was fronted by Mel Giedroyc and Sue Perkins, known as Mel and Sue.
Toksvig will still appear on the next series of The Great Celebrity Bake Off for Stand Up To Cancer, broadcast in the spring.Skip Twitter post by @BritishBakeOff Report End of Twitter post by @BritishBakeOff
Writing on Twitter Fielding said he now feels like "Tom without Jerry" and "Mick without a Keef".
On Instagram, he added : "Good double acts are a rare and magical beast! I'm gonna miss Sandi comically and personally but I also know we were lucky to have her for 3 amazing years! Wish you all the best in your next adventures x x love Noel x"
Channel 4's director of programmes Ian Katz said: "We are immensely grateful for Sandi's contribution to the show.
"We will miss her warmth and wit, not to mention her endless willingness to be the butt of jokes about being the least tall person in the Bake Off tent."
He added that the channel have other shows in development with Toksvig, "none of which involve cake".
Bake Off judge Prue Leith tweeted: "I have absolutely loved working with Sandi, she's been a brilliant host and enormous fun and I am in awe of how hard she works juggling so many different projects. We shall be lifelong friends way beyond the tent."
Leith joined the show in the same year as Toksvig and Fielding, with only Paul Hollywood staying on from the previous BBC line-up.
Writing on Instagram, Hollywood said: "I will miss Sandi, she has done an amazing job in the tent, much loved by all who met her. I wish Sandi continued success in all that she does XX."
Sandi Toksvig's statement in full:
"When stepping down from a job it is quite common for people to say they are doing so in order to spend more time with their family. Unusually I am departing from the Great British Bake Off so I can spend more time with my other work.
"As my waistline will testify, Bake Off is an all-consuming show. Spending time with Prue, Paul and Noel has been one of the great pleasures of my life. These are friendships which I know will continue beyond the confines of television.
"Bake Off is a wonderful programme which has already proved it can happily withstand a change of hosting personnel. The reason for that, of course, is that the true stars of the show are the bakers themselves. I wish everyone well."
The show's fans made clear that they will be sorry to see Toksvig go.Skip Twitter post by @elthampalacegay Report End of Twitter post by @elthampalacegay
The Great British Bake Off first aired on BBC Two in 2010, with Mel and Sue hosting and Mary Berry as one of the judges alongside Hollywood.
It became increasingly popular with viewers over several years and was promoted to BBC One in 2014.
The show remained there for another two years before Channel 4 outbid the BBC for the rights to broadcast it.
The first episode to air on Channel 4 gave the network .
The most recent series, broadcast last autumn, attracted about 9 million viewers per episode, with a consolidated audience of 9.7 million tuning in for the final.
The last episode to be broadcast on BBC One, which saw , was watched by about 14 million people.
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