Louis Walsh is to make a one-off return to 'The X Factor.'

Louis Walsh

Louis Walsh

The music manager, 63, who was axed from the show last year and replaced by Nick Grimshaw, will join the reality TV programme during rehearsals after he forked out a reported £20,000 in a charity auction at the Music Industry Trusts Awards in London last night (02.11.15).

An onlooker told the Daily Mirror newspaper that show boss Simon Cowell, who dropped Louis from the judging panel after 11 years, "looked shocked but stood up and laughed."

Despite paying out a five-figure sum to briefly rejoin his old show, it's believed Louis probably won't appear on screen.

Speaking about his former boss, who has 20-month-old son Eric with his partner Lauren Silverman, Louis said: "He has got a huge ego, he just wants to be the best, that's really what drives him. He's amazing in every way.

"He looks different, he walks different, he dresses different, everything is different about him. His face is different!"

Meanwhile, Simon, 56, has no made secret of the fact he would consider bringing Louis back as a guest judge.

He said previously: "I've got the ghost of Louis everywhere at the moment. What's so weird is that when he was on the show I'd always have people complaining about him and now he's gone it's like, 'Why isn't he there'. So I don't know what's going to happen. I couldn't just bring him back.

He added: "I do like the idea of maybe having a guest judge, something like that, that's a possibility."