Simon Cowell has paid tribute to his best friend Louis Walsh, but said sacking him from The X Factor nearly cost him their friendship.

The pair have worked together since 1998 when they launched top-selling Irish boyband Westlife.

But they are best known for their bickering on The X Factor judging panel.

Simon told the Daily Star: “Deep down, beyond work, Louis will be one of my best friends for ever… He is one of the funniest people I have ever met in my life.”

And it seems the feeling is mutual as Louis has said: “I love working with Simon. We’re like two brothers… When Simon walks into the room I just start laughing. He has this effect on me.”

The friendship was put under severe strain when Simon briefly sacked his Irish pal from The X Factor, to be replaced by American choreographer Brian Friedman.

Simon said: “He was devastated. I’ve never heard him sound like that, but the decision was made. He called me every name under the sun, he just unloaded and I didn’t feel great about it.”

But it didn’t take long for the music mogul to recognise his mistake.

He said: “It took me five minutes to realise how much I missed Louis. It wasn’t that the new person wasn’t very good, it was just I’d lost my buddy and I didn’t realise how much I liked having him there.”

Watch Louis Walsh: In My Life on Bio (Sky CH 156) Tuesday, 8 December at 9pm