Gold-medal winning athlete Mo Farah is reportedly set to sign up as a guest mentor on The The X Factor, according to The Sun.

The paper reports that Mo – who became a national hero after winning double gold at the London games in the 10,000 and 5000m – will take part in a special Olympics-themed show later in the series.

And he may even be joined by other members of Team GB once the live rounds begin, to offer advice to the finalists.

“Teaming up with our athletes means they can offer training and pep talks,” a source told the paper.

“People like Mo know about dedication and hard work. It’s only right we invite them to shape our future pop stars.”

The show returns to ITV1 tonight at 8pm with the first batch of auditions, and the chance to see guest judge Mel B join regulars Gary Barlow, Louis Walsh and Tulisa Contostavlos.

Meanwhile Mel B is being hailed as one of the toughest judges in show history, with a string of catty comments during the auditions which led Louis to nickname her ‘Grumpy Spice’.

The Spice Girls singer shocked the other judges with her tirade, which even led her to slag off an 82-year-old pensioner trying out for the show, as well as one of her own fans.

However Louis later admitted, “We liked the fact she was honest,” while newcomer Nicole Scherzinger added, “I thought it was funny. People are going to love her.”