BBC 1xtra DJ Sarah confirmed her departure in a message to fans via Twitter last night (11 May).
Sarah's news come amid reports that Simon Cowell is planning a major overhaul ahead of the new series of the ITV talent show, and Sarah referenced such "changes" as she announced her exit after one year.
She said: "Xtra factor has been amazing! However I have a new project coming up this summer & with all the changes happening I won't be back…. But I'm so excited to see the new line up and wanna wish them all the luck in the world... Can't wait to watch them in action!"
The official X Factor account tweeted: "We'd like to wish @DJSarahJane all the best and thank her for all her hard work on #XtraFactor."
It's been reported that there was a week of discussions before Sarah came to her final decision.
A source told The Mirror: "Sarah had two different meetings with X Factor bosses and lots of discussions this week. Everyone decided that this
was the best outcome."
Sarah was introduced as the new Xtra Factor host last year, replacing Caroline Flack.
Caroline's last series of Xtra Factor in 2013 was presented alongside comedian Matt Richardson, who was brought in to replace Olly Murs.
Sarah's exit follows on from the departure of long-standing judge Louis Walsh. After 11 years, it appears Louis will not be returning to the talent show, and Simon appeared to confirm it yesterday, by tweeting: "Louis Walsh is one of the good guys. We will always be friends. The door remains open and who knows what's next..."
Meanwhile, Dermot O'Leary also stepped down as host of the main show after eight years, but it was announced last month that former Xtra Factor duo Olly and Caroline would replace him on the main stage.
Auditions for the new series are already underway.
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