The X Factor USA judge LA Reid has admitted that his biggest professional regret was passing on the opportunity to sign Lady GaGa early in her career.

Appearing on The Ellen DeGeneres Show, the former Island DefJam record label boss revealed that he had initially been enthusiastic about GaGa - telling her she would "change music" - but later cooled after hearing a demo tape.

He explained: "I said, 'You know what? This is disgusting'… and I dropped her and I dropped [her A&R guy].

"It was the biggest mistake I ever made in my life."