LONDON (AFP) -- The British government and police faced fresh pressure over their ties to Rupert Murdoch on Saturday as the media mogul published apologies in national newspapers over the phone hacking scandal.

A day after Murdoch lost two of his most senior executives, the crisis returned to haunt the British establishment with new allegations about the close ties between the media baron's empire and the police and politicians.

Prime Minister David Cameron was forced on the defensive after it emerged that he personally had 26 meetings in 15 months with key figures Murdoch's News Corp. and its British newspaper division, News International.

Scotland Yard was meanwhile drawn deeper into the row with the revelation that Commissioner Paul Stephenson met Murdoch executives and editors 18 times socially between 2006 and 2010.

This included a dinner with the deputy editor of the News of the World in September 2006, when the police force was investigating hacking at the tabloid, and when Stephenson was deputy commissioner.

A spokesman told AFP that meetings with the media were a "necessary part" of being a senior police officer.

But the revelation is likely to up the pressure on Stephenson, who is already facing questions about why the force hired a former News of the World deputy editor, Neil Wallis, as an advisor just two months after he quit the tabloid.

Wallis was arrested last week over the phone hacking scandal.

Scotland Yard has previously defended its links with Wallis, and a spokesman strongly denied fresh claims by Sky News television late Saturday about a free stay Stephenson had accepted from a health clinic and spa where Wallis worked.

"The commissioner only learnt who the PR consultant for Champneys was following a media enquiry today," he said, adding that Stephenson's meals and accommodation were provided by the spa's managing director, a personal friend.

Stephenson has been called to give evidence on Tuesday to a committee of lawmakers which last week grilled other senior officers about the phone hacking investigation, alleged payments to police and their ties to News International.

The government meanwhile has also been forced to defend its links to Murdoch's empire.

It has emerged that Cameron hosted former News of the World editor Rebekah Brooks, who quit Friday as chief executive of News International, and Murdoch's son James, the chairman of News International, at his country retreat, Chequers.

"Personally, I'm not embarrassed by it in any way," Foreign Secretary William Hague told the BBC on Saturday after widespread media criticism.

Hague also defended Cameron's decision to invite Andy Coulson, his former media chief and another one-time editor of the News of the World tabloid, to Chequers in March, two months after Coulson quit Downing Street.

Coulson was arrested last week in connection with the scandal over alleged hacking and payments to police, one of nine people held since police reopened their investigations in January. He denies the charges.

Hague said: "In inviting Andy Coulson back, the prime minister has invited someone back to thank him for his work, he's worked for him for several years, that is a normal, human thing to do."

On Saturday, Murdoch abandoned his previously defiant stance and ran full-page adverts in seven national British dailies, apologising for the hacking scandal at the News of the World, which he closed down last week.

"We are sorry," the headline of the ads read. They were signed "Sincerely, Rupert Murdoch."

In a further show of contrition, Murdoch on Friday met the parents of murdered teenager Milly Dowler, whose phone was allegedly hacked by the News of the World in 2002, when Brooks was editor of the paper.

Murdoch's determination to keep his empire afloat was shown, however, when he accepted the resignation of Brooks on Friday and then, hours later that of Les Hinton, head of Dow Jones, the publisher of The Wall Street Journal.

Both Brooks and Hinton, a former chairman of News International who had worked with Murdoch for 50 years, deny any knowledge of the phone hacking.

Their departure capped a disastrous week for Murdoch in which he was also forced to scrap a buy-out of British pay-TV giant BSkyB, and also leaves his heir-apparent James, 38, exposed.

The British government has announced a full public inquiry into the scandal, and Rupert Murdoch, James Murdoch and Brooks have all been summoned to testify before British lawmakers on Tuesday.