Robbie Williams and Ayda Field spent their first day on 'The X Factor' judging panel mocking one another.

Robbie Williams and Ayda Field

Robbie Williams and Ayda Field

The couple - who are joined by Louis Tomlinson and show boss Simon Cowell this series - put their relationship on display during the London auditions for the upcoming series, with no subject off limits for their jibes.

As they talked about one hopeful's pet, Robbie made a joke about sex toys as he quipped: "Ayda's got a rabbit."

His wife blushed and said: "Different kind, Rob, different kind of rabbit."

The 44-year-old singer laughed and said: "Let's not go there now."

The 39-year-old actress - who has children Teddy, five, and Charlton, three, with Robbie - also mocked the 'Angels' hitmaker for his failure to crack America.

After one auditionee said he wanted to be a major artist in the UK, Ireland and the US, the 'Loose Women' panellist joked: "You got two out of three, babe!"

When Robbie told one contestant she had lost his attention after just a minute, Ayda quickly retorted: "He's got attention deficit disorder, so you're lucky you got him for the first minute."

And she told another hopeful: "In my mind I was in one of your music videos and kept thinking how good it would be if Robbie opened for you! You are amazing."

Audience members at the SSE Arena, Wembley, in north London, were impressed by the couple's performance on the panel.

One told The Sun newspaper's Bizarre TV column: "It just worked. They're going to be the stars of the series, the way they work together is just really funny and natural.

"They went down a storm and Ayda had no problem sticking up for herself.

"She even got a few cheeky digs in at Simon Cowell."

But it wasn't all jokes at the auditions as Robbie was brought to tears when Janice Robinson, who sang on Livin' Joy's 1994 single 'Dreamer', performed for the panel.

He said: "That song means so much to me as it is the soundtrack to my party days -- which had a lot of ups and downs."