LONDON - Phone-hacking allegations spread beyond the fallen News of the World to other British tabloids on Saturday, though the claims were strongly denounced by their proprietors.

Former journalists at the Daily Mirror and Sunday Mirror - the main tabloid competitors to Rupert Murdoch's British stable - reportedly said the illegal hacking of voicemails was widespread at their papers too.

The scandal has also rocked the British police and even given Prime Minister David Cameron a rough ride, but has so far largely been limited to the News of the World, which Murdoch shut on July 7 amid public outrage.

James Hipwell, a former Daily Mirror financial journalist jailed in 2005 for buying shares before tipping them in the paper, said he was aware of hacking because he worked next to the showbusiness desk where it was rife.

"You know what people around you are doing," the 45-year-old told The Independent newspaper.

"They would call a celebrity with one phone and when it was answered they would then hang up. By that stage the other phone would be into their (the celebrity's) voicemail and they would key in the code."

"There was a great hilarity about it."

Hipwell worked at the Mirror for two years until 2000 when it was under the editorship of Piers Morgan, himself a former News of the World editor. Hipwell was sacked by the Mirror over the so-called "City Slickers" scandal.

Morgan, who is now a presenter for US television news network CNN, has denied having any knowledge that phone hacking went on under his editorship and came out fighting on Saturday.

He made a fresh demand for an apology from Louise Mensch, a British lawmaker on a parliamentary committee which quizzed Rupert and James Murdoch on Tuesday, who claimed during the hearing that Morgan had admitted to phone hacking.

"Now then Louise Mensch - will you be making (a) public apology for your lies in parliament about me, or do I have to write to (committee chairman) John Whittingdale?" Morgan said on Twitter.

"You could just have the guts to accuse me of phone hacking outside of parliamentary privilege, and see how you get on."

Separately the BBC quoted an unidentified former Sunday Mirror journalist who worked on the paper in the past decade and claimed to have witnessed routine phone hacking in the newsroom.

Trinity Mirror, the group which publishes both papers, said its journalists work within the law and the code of conduct of Britain's self-regulatory Press Complaints Commission.

It said Hipwell's allegations were "totally unsubstantiated".

On Thursday it emerged that police had requested files from a British data protection regulator which published a report showing the non-Murdoch Daily Mail, the Mirror and the Trinity Mirror-published The People were the biggest users of private investigators to seek confidential information.

Meanwhile police are to investigate claims of phone hacking in Scotland, which has its own legal system, and whether witnesses lied during a perjury trial last year.

Former News of the World editor Andy Coulson - who went on to become Cameron's media chief before resigning and being arrested this year - was among those who gave evidence.

On Saturday, The Daily Telegraph newspaper said that George Osborne, Britain's finance minister, dined with Rupert Murdoch in New York in December, two weeks before Britain's media regulator was originally due to decide on whether to approve Murdoch's bid for full control of pay-TV giant BSkyB.

Murdoch's US-based News Corp was forced to abandon a bid for full control of the lucrative pay-TV satellite broadcaster earlier this month because of the scandal.

The Treasury refused to discuss who attended, but insisted that BSkyB was not discussed.

The Daily Telegraph also said that Lord Brian Leveson, the judge in charge of the phone-hacking inquiry, went to two parties in the last year at the home of Matthew Freud, a public relations executive married to Murdoch's daughter Elisabeth.