Sir Tom Jones is reportedly planning to quit 'The Voice UK'.

Sir Tom Jones

Sir Tom Jones

Although the 76-year-old star has been vocal about his enthusiasm for the show - after re-joining the panel when it moved from the BBC to ITV - he is believed to have told friends that he won't be back next season.

A source told The Sun on Sunday: "Tom has really loved being back on 'The Voice', and is having a great time working with the other judges and the entire team.

"They all get along famously behind the scenes, as well as on camera.

"But there's no denying that filming show is very hard work, and takes up a huge amount of time and energy. Tom has really felt that this year.

"He has found it very tiring. And he has been overheard telling his team that he 'already knows' he won't be back for the next series, because it takes too much out of him."

However, Tom has not officially quit and ITV are working on a plan to get him to stay.

The insider added: "After being so unceremoniously dumped from the BBC show, Tom returned to 'The Voice' on ITV with a whole new enthusiasm.

"But while he has thoroughly enjoyed himself, that has come at a cost. And at the moment he seems to feel that he would like to go out on a high.

"Nothing has been decided yet, and ITV are hoping they can change his mind.

"But if not, they will just have to go back to the drawing board."

Tom co-stars on the show with Jennifer Hudson, Gavin Rossdale and will.i.am.