The X Factor could be about to welcome a fifth judge to the panel to mentor a "wild card" category.

Bosses at the ITV singing contest are said to be considering the surprise addition to shake up the panel again and look after four wild card acts, according to The Sun.

Potential judges thought to be in the running to take on the new category include Rita Ora and Mary J Blige, who would join the already confirmed line up of Simon Cowell, Louis Walsh, Cheryl Cole and Mel B.

The odd number of judges would mean that there would always be a judges' choice when it came to the elimination vote, taking away the possibility of the decision going to deadlock where it is left up to the public vote.

X Factor boss Simon is said to be keen to boost the show's flagging ratings, which have dropped since he last appeared as a judge in 2011.

A spokesman for the programme said: "No decisions have been made regarding the live shows at this stage."