Welsh singing legend Tom Jones says judges on The X Factor make bad decisions because they don’t have enough experience of the music industry.

Jones, 71 - who joins Jessie J, will.i.am and Danny O'Donoghue as a coach on BBC1’s upcoming new talent show The Voice UK - said The X Factor had failed to discover “stars with world-class voices" and that the show's judges had made numerous wrong decisions.

"Every time I see one of these shows I think half the decisions are wrong and it really frustrates me,” said Jones.

"Some of the judges don't have the experience to be on talent shows - if you've only been in the industry two minutes, how can you offer advice?” asked the singer, whose career spans five decades.

“I have the experience and I listen to all sorts of music, so the advice I give will be valuable,” he told The People.

Jones said he had agreed to join The Voice because he felt he could do a better job than judges on existing shows, and because its format - which features initial rounds in which contestants are heard but not seen - is about discovering real vocal talent.

"I got fed up with shows like X Factor and thought I better do one myself because the judging has been questionable. A singing contest should be about someone's voice - not PR spin," he said.

"I'm genuinely excited about The Voice - it's exciting, competitive and compelling television because it's all about talent."

Jones is not the first UK Voice coach to openly attack The X Factor. Black Eyed Peas star will.i.am previously said he hoped former X Factor judge Cheryl Cole, who he manages, would perform on The Voice to "p*** Simon Cowell off."

Start dates for the two shows have not yet been confirmed but reports suggest they could go head-to-head on 24 March. 

The judging line-up for the new series of The X Factor is still to be announced but long-time panellist Louis Walsh has suggested that he, Gary Barlow and Tulisa will retain their places. Kelly Rowland is thought not to be returning. 

The Voice UK is based on a Dutch format and is already a huge success in the United States.