Veteran X Factor judge Louis Walsh said the new judges have given the show "a whole new energy" at last night’s preview at the O2 Greenwich last night.

The Irishman, who described himself as "the last judge standing", has been joined by Tulisa Contostavlos, Gary Barlow and Kelly Rowland on the judging panel on the hit ITV1 show.

The trio replaced Cheryl Cole, Dannii Minogue and Simon Cowell who is busy with his US version of the show.

Speaking at a press preview for the show at the O2 in Greenwich, south London, Walsh said: "I couldn't do a real job, I love this job and this year is different - there is a whole new energy to the show.

"It's like having a brand new car with a whole new engine. It's bigger and better.

"I can't explain, yes I miss Simon and Dannii and Cheryl but these guys have brought something new."

Walsh has also struck up an unlikely friendship with Tulisa.

She said: "It's a strange relationship - kind of like a father/daughter relationship, but we're best friends, so it's quite funny. I don't think there's any way to describe it properly because the chemistry is rather strange."

The show starts on ITV1 at 8pm on Saturday.