Nick Knowles could be breaking BBC guidelines when he appeared on a Shreddies ad, according to sources.
The DIY SOS star is in “absolute agony” over the possibility of losing his job when he appeared on an advertisement for the grain.
The 30-second ad in which he calls himself “Nick get it done Knowles” first aired in February.
It is shown regularly on television and viewed online more than two million times.
Nick hosted DIY SOS from the start in 1999 and it quickly became a hit.
In each episode, a team of builders and volunteers transform a home for a person nominated by their friends and family.
Last year, he and the team raised nearly £ 1 million for children in need with their big build.
Nick previously admitted that the show regularly brought him to tears.
But he could be kicked off the show, according to sources who say it could have landed him in hot water.
A source told the Sun: “Nick is absolutely tormented by the whole situation because he loves the Beeb.
“But they have very strict guidelines when it comes to their talent and promotion, and he’s already broken them by filming the ads. But shreddies don’t want to pull the campaign.
“While Nick is technically a free agent, he appears to have used his connection to DIY SOS in advertising, which is completely out of order in the eyes of the BBC.
“Nick was basically given an ultimatum and the decision may already be in his hands.”