Ant and Dec have pulled out of upcoming work commitments due to sudden illness.
The presenting duo were set to film a Britain's Got Talent special called The Ultimate Magician.
They confirmed on Twitter they have tested positive for Covid.
A Britain's Got Talent Spokesperson told ITV Tyne Tees News: "Ant and Dec are both unwell and have postponed all work commitments until they recover. Sadly, this means they were unable to film Britain’s Got Talent: The Ultimate Magician."
ITV had announced the new spin off on Monday writing online: "Over the past 16 years, we’ve witnessed some of the most mesmerising and spellbinding magical acts take to the Britain’s Got Talent stage.
"Now, they’ll go head-to-head with some of the world’s most talented magicians in Britain’s Got Talent: The Ultimate Magician."
Since Ant and Dec have dropped out of upcoming work commitments, the show has been forced to appoint a new presenter.
A spokesperson for Britain's Got Talent, said: "Whilst we wish them a speedy recovery, we are thrilled to confirm that BGT’s favourite magician, Stephen Mulhern has stepped in."
The pair have also confirmed they will not attend the National Television Awards, where they have been nominated for their 21st NTA presenter award.
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