Labour leader Ed Miliband called on British Prime Minister David Cameron on Friday to admit the "appalling error of judgment" he made in hiring former News of the World editor as his director of communications, as the fallout from the paper's phone hacking scandal spreads.
British media report that Cameron's former director of communications, Andy Coulson, is expected to be questioned by investigators over his suspected involvement in the hacking practices that took place while he was editor of the paper.
The fallout could have far-reaching and politically damaging consequences for Cameron.
He is close to current and former top officials at the News of the World's parent company, former Tony Blair spokesman Alastair Campbell told CNN Thursday.
Miliband said Cameron must "come clean" about conversations he had with Andy Coulson about phone hacking, before and after appointing him as his communications chief.
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On Thursday, the News of the World's parent company, News International, made the shock announcement that Sunday's edition of the scandal-hit tabloid would be its last.
But Miliband pressed for further changes. He said the system of self regulation through the Press Complaints Commission has failed -- describing the press watchdog as a "toothless poodle" -- and needs wholesale reform. A new body with more independence is needed, he said, to restore the reputation of British journalism.
He also said politicians must take some of the blame for letting sections of the media gain too much power.
"For too long, the political class have been too concerned about what people in the press would think and too fearful of speaking out," he said, rather than standing up for the rights of the people.
And he urged senior executives at News International, including chairman James Murdoch, to take responsibility for the scandal.
"I welcome James Murdoch's admission of serious errors. But closing the News of the World, possibly to re-open as the Sunday Sun, is not the answer.
"Instead those who were in charge must take responsibility for what happened."
The remarks follow accusations that the News of the World illegally eavesdropped on the phone messages of murder and terror victims, politicians and celebrities, and claims it may have bribed police officers.
According to British media, Coulson has been told by police that he should go to a police station to be arrested on Friday morning over his knowledge of or involvement in mobile phone-hacking practices that took place in the four years he ran the paper.
The media also speculate that he is likely to be released on bail and appear in court at a later date alongside other arrested former News of the World journalists.
He resigned as editor in January 2007 after the News of the World royal editor Clive Goodman and a private investigator, Glenn Mulcaire, were jailed for intercepting voicemail messages on royal aides' phones.
After moving to his communications role with the Conservative party, the scandal resurfaced.
Coulson was questioned by police in November and resigned from his Downing Street position in January this year, despite the Crown Prosecution Service ruling that there was "no admissible evidence" to bring criminal charges.
Prime Minister Cameron Wednesday called the possibility that the hacking had taken place "absolutely disgusting" and backed calls for an independent inquiry into the affair after a police investigation concludes.
Questions are also mounting over the future of News International's chief executive Rebekah Brooks, who was editor of the News of the World at the time some of the alleged phone hacking took place.
News International Chairman James Murdoch said Thursday, in announcing the shutdown, that the scandal "sullied" the newspaper and "has no place in our company."
And paying out-of-court settlements to some victims was "wrong and a matter of serious regret," Murdoch said. He is a son of media magnate Rupert Murdoch, the head of News Corp., which owns News International.
The paper's roughly 200 employees are now out of jobs, but are free to apply for other positions within News International, the company said. The layoffs have angered union representatives.
On Wednesday, Rupert Murdoch himself called allegations against his flagship Sunday paper "deplorable and unacceptable."
News of the World was the first British Fleet Street newspaper Rupert Murdoch bought, in 1969, as he began to propel himself from Australian newspaper proprietor to international media magnate.
In addition to owning News of the World, News International owns the Sun, the Times and the Sunday Times in Britain.
Murdoch's News Corp. also encompasses Fox News, the Wall Street Journal, the New York Post and Harper Collins publishers.