The BBC Radio 1 Breakfast Show presenter – who has also left the programme this year – reacted to Cheryl's departure while on air on Tuesday (5 April).
Cheryl's exit from the ITV1 talent show came after co-hosts Caroline Flack and Olly Murs also stepped down, and original presenter Dermot O'Leary confirmed he would be returning.
"She is off, I'm off, Simon's on, Dermot's on, then who else? Olly's gone, Caroline's gone, the interest is gone. Just kidding! Just kidding!" he joked.
In a statement this morning, Cheryl said: "I have had such an amazing experience being a judge on The X Factor. I have learnt so much and enjoyed nurturing talent but I've missed making music and am excited to be recording again.
"I want to thank everybody I have worked with along the way, especially Simon who I love to bits. I hope the show continues to produce stars and I wish them all the best."
Cheryl originally joined X Factor in 2008 for its fifth series, and won with her contestant Alexandra Burke. She won the following year with Joe McElderry.
The Girls Aloud star left ahead of the eighth series to move to the US and appear on the judging panel for X Factor USA's debut series, but was let go after just a few days of filming, causing a row between her and Simon Cowell.
But they later repaired their friendship and she returned in 2014.
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