The comedian was sent home from rehearsals after contracting tonsillitis and has been told by organisers to refrain from talking in order to recover before Wednesday's (February 20) show.
"James has been really excited about presenting the Brit Awards and doesn't want to have to pull out so getting better in time for the big night is his number one priority," a source told The Daily Telegraph.
However, a spokesperson for Corden has denied the severity of the illness, saying the situation has been "greatly overplayed".
This year will mark the fourth year Corden has hosted the Brit Awards. The ceremony will take place at London's O2 Arena on Wednesday, February 20.
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