Jack Osbourne claims that he was fired via email after his multiple sclerosis diagnosis was announced.

The Adrenalin Junkie host – and son of rocker couple Ozzy and Sharon Osbourne – says that an undisclosed television dumped him from a job after deciding that he would be unable to perform tasks in a planned reality contest.

Jack – who was diagnosed with the condition five weeks ago, but revealed his diagnosis earlier this week – said on The Talk: "I had booked a job, right when I got diagnosed and the company didn't think I could actually perform the job.

"Out of everything, that's what has really ticked me off the most because it's like, 'Don't tell me what I can and cannot do.' At no point did they call me.

"It was all through agents and lawyers - I was offended by it."

Sharon took to her Twitter account to hit back at the company, saying that Jack was told that he was a "liability".

She wrote: "Yes @MrJacko was fired. They said he was a liability & were so personable, sent an email to let us know."

It is believed that the show in question was Stars Earn Stripes, which sees soldiers put celebrities through a series of military exercises.

A source on the show told The Sun that producers felt Osbourne would not be able to handle the challenges, but said it was "hard to believe" that he was informed by email.