James Murdoch was under pressure Saturday over the extent of his knowledge of Britain's phone-hacking scandal as accusations of tabloid wrongdoing spread beyond the felled News of the World.

Prime Minister David Cameron, facing a rough ride over his appointment of former NotW editor Andy Coulson as his media chief, said Murdoch had "questions to answer" over claims of misleading parliament on the affair.

James Murdoch, the chairman of News International, the British newspaper division of his father Rupert's News Corporation global media empire, has been challenged over evidence he gave before parliament's media scrutiny committee on Tuesday.

A lawmaker has referred James Murdoch's testimony to the police. He is standing by his evidence.

During a tense appearance with his father before the committee, James Murdoch said that when authorising an out-of-court settlement to a voicemail hacking victim, he was unaware of an email that could suggest knowledge of hacking at the now-shuttered NotW went wider than one rogue reporter.

But Colin Myler, the last editor of the News of the World, and Tom Crone, the former News International legal manager, broke ranks on Thursday to say James Murdoch's recollection of events in 2008 was "mistaken".

The scandal, which erupted earlier this month, has already engulfed News International, the police and senior politicians, including Cameron.

So far the allegations of wrongdoing have largely been restricted to News of the World.

However, a former journalist at the Daily Mirror tabloid -- the main competitor to News International's The Sun, Britain's biggest-selling newspaper -- claimed that voicemail hacking was widespread at his old paper.

James Hipwell, 45, worked for two years until 2000 on the tabloid's business desk, which he said was next to the showbusiness desk.

"You know what people around you are doing," he 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.

"At the time it wasn't illegal... It was seen as a bit of a wheeze, slightly underhand but something many of them did -- what a laugh.

"After they'd hacked into someone's mobile they'd delete the message so another paper couldn't get the story. There was a great hilarity about it."

Hipwell was sacked by the Mirror over the so-called "City Slickers" scandal. He was accused of buying shares before tipping them in the paper. He was convicted of market manipulation and jailed.

A spokesman for the tabloid's publishers Trinity Mirror insisted: "Our journalists work within the criminal law and the Press Complaints Commission code of conduct."

Meanwhile police are to investigate claims of phone hacking in Scotland, which has its own legal system.

They are also investigating whether witnesses lied during a perjury trial last year.

Coulson, the Scottish News of the World editor and a reporter were among those who gave evidence.

Opposition Labour Party leader Ed Miliband told The Times that the newspaper's owners News International needed to do more to break with the past.

"There are just too many unanswered questions. The ignorance defence is being used too often in this saga, at the top of News International and by politicians," he said.

"It gets to a point where the sin of not finding out is as bad as finding out."

He said it was down to News International and its investors to decide whether James and Rupert Murdoch should resign, but added: "this happened on someone's watch".

News Corp. was forced to abandon a bid for full control of the lucrative pay-TV satellite broadcaster BSkyB giant earlier this month because of the scandal.

The Daily Telegraph newspaper said Saturday that British finance minister George Osborne had dinner with Rupert Murdoch in New York in December, two weeks before the media regulator was originally due to decide on whether to approve the his BSkyB takeover bid.

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

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