British Prime Minister David Cameron called an urgent news conference on Friday after reports his former spokesman was meeting police and could be arrested after the closure of the scandal-hit newspaper he once edited.
Underlining the political impact of the phone-hacking allegations which prompted Rupert Murdoch to shut down the best-selling News of the World tabloid, Cameron's office said he would take questions from reporters at 9:30 a.m. (0830 GMT).
Police have arrested several journalists in recent weeks after reopening inquiries into the hacking of cellphone voicemails, for which the paper's royal correspondent and a private investigator were jailed in 2007. But they declined to comment on media reports that Andy Coulson, Cameron's spokesman until January, was also about to be arrested.
Murdoch's Times newspaper said on its website that Coulson had arrived at a London police station to face questions over the phone hacking scandal.
Coulson resigned as editor of the News of the World after the convictions in 2007 but has sworn he knew nothing of the practice of monitoring the cellphone mailboxes of celebrities.
Hired almost immediately by Cameron to run his media efforts, Coulson became a key figure in Downing Street when the Conservatives won a general election last May, ending 13 years of rule by Labour -- which, some said significantly, had lost the support of Murdoch's News International press stable.
The renewal of police inquiries in January, as News Corp acknowledged evidence that phone hacking was more than just the work of one rogue reporter, prompted Coulson to quit the prime minister's office, still protesting his innocence.
Cameron's judgment has come under fire for hiring Coulson, as well as for his friendship with Rebekah Brooks, Coulson's predecessor in the editor's chair and now a close Murdoch confidante who is defying calls to resign from his company.
In a breathtaking response to the scandal engulfing the global media empire, the British newspaper arm of News Corp announced it would publish the 168-year-old News of the World, the best selling Sunday title in the country with some 7.5 million readers, for the last time this weekend.
Hacked To Death headlined Murdoch's own Times newspaper in London. Paper That Died Of Shame was the verdict of the Daily Mail, a rival tabloid title.
As allegations multiplied that News of the World journalists hacked the voicemail of thousands of people, from child murder victims to the families of Britain's war dead, the tabloid hemorrhaged advertising, alienated readers and posed a growing threat to Murdoch's bid for broadcaster BSkyB.
Analysts estimate -- though full accounts are not published -- that the newspaper made perhaps some 10 million pounds ($16 million) a year on sales of 2.7 million copies a week, compared to perhaps 100 times that which Murdoch could hope to earn from full control of the Sky pay-TV chain in Britain.
The scandal, as it erupted this week with allegations that phone-hacking extended to victims of crime, has given new heart to those, especially on the left, who want to block News Corp's 14-billion-pound bid for the 61 percent of Sky's owner BSkyB which it does not already own.
Analysts believe the deal is still likely to go through, given that Cameron's government has already given its blessing in principle. There is still no deadline for approval, however, and some market experts believe political uproar could still thwart the deal, whatever the legal technicalities of approval.
Labour opposition leader Ed Miliband said: Given the doubts hanging over the assurances about phone hacking by News International executives, doubts which grow by the day, I cannot see, and the public will not understand, how this process can provide the fair dealing that is necessary.
I strongly urge the government to take responsibility and think again about how it is handling the BSkyB decision.
Murdoch, the 80-year-old Australian-born media mogul, is an object of fear among British politicians, using his newspapers, which include the biggest selling daily the Sun as well as London's Times, to set political agendas and capable of swaying at least some votes by apportioning approval to right or left.
Miliband said closing a newspaper which many expect will be quickly, and more economically, replaced by a Sunday edition of the Sun, was not enough to answer the allegations of crimes that also include bribing police officers for information.
And he called again for Brooks, 43, to resign as chief executive of News International. She denies knowledge of some of the gravest instances of phone-hacking alleged to have been committed while she ran the paper a decade ago -- including that an investigator tapped into -- and deleted -- voicemails left for a missing schoolgirl who was later found murdered.
Brooks has become a lightning rod for anger among the 200 News of the World staff sacked with little ceremony on Thursday. There was seething anger and pure hatred directed toward her, one reporter said: We think they're closing down a whole newspaper just to protect one woman's job.
The ruthlessness of the decision, announced by his son and heir apparent James Murdoch, was a dramatic turn in Murdoch's long and controversial career which now spans the globe and includes Fox television and the Wall Street Journal in the United States and major broadcasting operations in Asia.
In his native Australia, the influential Greens Party called on the government to investigate Rupert Murdoch's media holdings in that country. The Greens, who hold the balance of power in the upper house of parliament and whose political backing is vital to the minority Labor government, asked for an official inquiry into News Corp's local operations.
James Murdoch said the News of the World, which his father bought in 1969, had been sullied by behavior that was wrong.
Indeed, if recent allegations are true, it was inhuman and has no place in our company, he said in a statement.
The Internet domain name sunonsunday.co.uk was registered on Tuesday by a British individual who opted to remain anonymous, according to domain names look-up service Who.is, reinforcing speculation the News of the World would be replaced by the Sun publishing on seven days rather than its present six.
Last month, Brooks prepared the ground for seven-day working across News International's four titles, and appointed two new managing editors, one with responsibility for the tabloids and one for the broadsheets. Other publishers have also tried to cut costs by merging Sunday and daily operations.
Where there is common ground we will find ways of implementing efficiencies to editorial systems and processes and, where appropriate, we will find ways of introducing seven day working, Brooks said in a statement at that time. ($1 = 0.622 British Pounds)
(Additional reporting by Georgina Prodhan, Kate Holton and Tiffany Wu; Writing by Janet Lawrence and Alastair Macdonald; Editing by Philippa Fletcher)