R Kelly's 'Ignition' was originally about underage girls - former lawyer

The former lawyer for embattled singer R Kelly has given a damning interview.

Ed Genson defended the 'I Believe I Can Fly' hitmaker in 2008, when he was facing child pornography charges.

But the 77-year-old has now told the Chicago Sun Times his former client - who back then, was acquitted - is "guilty as hell".

Mr Genson, who is dying of terminal cancer, told the newspaper he's running out of time to set the record straight.

"He was guilty as hell!"

But Kelly's offending was all in the past, he said.

"I don't think he's done anything inappropriate for years. I'll tell you a secret: I had him go to a doctor to get shots, libido-killing shots. That's why he didn't get arrested for anything else."

Mr Genson said Kelly's lawyer "might be… an idiot" for letting his client be interviewed by CBS News.

He also said he vetted dodgy lyrics about young girls before Kelly could release them - including one of his biggest hits, 'Ignition'.

"I was riding in the car, listening to a song and said, 'Are you crazy? This is all I need.' He re-wrote it."

'Ignition' was originally about a high school teacher and a student, Mr Genson said, adding that Kelly was "not a very bright person".

Kelly has always denied the accusations, despite video evidence and the sheer number of accusers.

He's currently facing 10 charges.