05/11/2012 11:06 GMT | Updated 05/11/2012 12:43 GMT

Tory Child Sex Abuse Claim: David Cameron Announces Inquiry Into 'Dreadful' Allegations

David Cameron has ordered an inquiry into allegations that a senior Thatcher-era Tory political figure sexually abused children, and that it was covered up.

The prime minister said on Monday afternoon that an independent figure would be appointed to investigate the conduct of the the initial inquiry into claims of child abuse in North Wales care homes in the 1970s.

"These allegations are absolutely dreadful and they musn't be left hanging in the air," he said.

"I'm going to be asking a senior independent figure to lead an urgent investigation into whether the original inquiry was properly constituted and properly did its job and to report urgently to the government."

The move comes three days after the BBC's Newsnight programme broadcast allegations that a leading Tory had sexually abused boys in care. However the corporation decided not to name the figure.

Steve Messham, who said he had been the subject of abuse, told Newsnight it was time for a full investigation took place into the potential cover-up.

He claimed that the first inquiry into abuse linked to the Bryn Estyn care home had ignored allegations that a senior Tory political figure was involved.

"In the home it was the standard abuse which was violent and sexual. Outside it was like you were sold, we were taken to the Crest Hotel in Wrexham, mainly on Sunday nights, where they would rent rooms," he said.

"One particular night that I always recall is when I was basically raped, tied down, and abused by nine different men."

He said: "You were taken by car, where basically you were sexually abused. Various things would happen, drink would be involved, it was basically rape. But it wasn't just him, there be other people involved as well.

Messham also said that when he went to the police to report the abuse he was ignored. "I was called a liar. I was pinned up against a wall. I could still name to this day the police officer who had done it," he said.

Labour MP Tom Watson, who has taken a leading role in the campaign to expose the abuse, wrote a letter to on Monday to Cameron demanding a police investigation.

"If what you really want – and I believe that it is – is the truth, then you must draw the terms of reference such that the police inquiry has licence to follow any lead it finds in what will be, after all, a serious criminal investigation," he said.

"Your advisers will tell you to be wary of 'opening the floodgates'. They are wrong. Their decorous caution is the friend of the paedophile.

"Narrowing the inquiry equals hiding the truth. That is the reality and it is not what you want."