The ‘No Strings Attached’ - who is married to Demi Moore - has been approached to take on the vacancy left when troubled star Charlie was fired from the show earlier this year because of his turbulent private life.

And he has appeared to confirm the news on his twitter account.

He tweeted "what's the square root of 6.25?" leaving his twitter followers to believe the answer 2.5 is a confirmation that he is taking on the role.

According to The Hollywood Reporter, writer Chuck Lorre has reportedly created a hilarious storyline to introduce the 33-year-old actor to viewers, with sources revealing he will receive a “huge payday” to join the long-running series.

A source said: “It’s really funny. People are going to love it. Chuck's really happy."

A number of high profile stars –including Rob Lowe, Woody Harrelson, Jeremy Piven and John Stamos – have all been tipped to take over from Charlie on the sitcom with British star Hugh Grant recently turning down the job due to "creative differences".

According to insiders, creator and executive producer Chuck - who Charlie branded "s**tbrain and "Chucky Cheesball" during their public feud - will only continue the show if he can find someone to work comfortably with.

A source told website "Chuck will only continue if he can find the right actor and get excited about that. It has to be somebody Chuck can work with.”

Warner Bros. and network CBS are keen to get the matter resolved soon in order to get a new series of the show ready before the end of the year.

A source said: "Everybody wants show back and to support Chuck creatively and to do something the advertising community will feel good about. The only issue was whether everyone could get the show up and running and right fast enough to make this fall's schedule."

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