MasterChef host Gregg Wallace has denied allegations of inappropriate sexual comments he is said to have made to a female colleague.

The Sun reported that Wallace was reported to BBC bosses after he was accused of taking his top off and boasting about his sex life to a woman on the show Impossible Celebrities in 2018.

But in an Instagram story posted on Monday, Wallace said the incident had been investigated at the time, and that the outcome was that “I hadn’t said anything sexual”.

The BBC said it does not tolerate “any form of inappropriate behaviour” and has “robust processes” in place.

Wallace has been approached by the BBC for a comment.

According to an unnamed source in The Sun, Wallace was accused of making “consistent inappropriate comments” to the younger woman while they worked on the panel show.

“Gregg appeared to think it was all just banter and is also said to have made some comments in front of the live audience,” the source said.

He is also said to have been talking about his sex life with his partner at the time.

“The team working on the show were mortified and told BBC top brass what had happened,” the source said.

Wallace took to social media on Monday to respond to the claims, posting two Instagram stories.

In the first one, he said the story “was investigated promptly when it happened six years ago by the BBC and the outcome of that was that I hadn’t said anything sexual.

“Do I need to repeat this again? I didn’t say anything sexual. Thank you for your time.”

He then posted a second story, in which he said: “Nobody six years ago accused me of flirting with anybody or hitting on anybody.

“The reason I say this is because of my wife Anna. I have always been true to my wife Anna.”

He added that he had “never flirted or hit on anybody” in the twelve years that he has been with his wife.

“It’s important that, so that people don’t misunderstand that, that I am true to my wife.”

Wallace is best known for co-presenting cooking show MasterChef.

The allegations come at a difficult time for the BBC. Earlier this year, the corporation’s former most senior news presenter, Huw Edwards, received a suspended jail sentence after pleading guilty to child sex abuse image offences.

In August, Jermaine Jenas, who presented The One Show and appeared on Match of the Day for the BBC, was sacked by the corporation following complaints about workplace conduct.

A BBC spokesperson said: “Whilst we do not comment on individuals, if issues are raised they are dealt with swiftly and appropriately at the time. We do not tolerate any form of inappropriate behaviour and have robust processes in place.”