Rupert Murdoch completed a reputation-shredding week in British political and media circles by accusing senior figures at the News of the World of orchestrating an elaborate cover-up over phone hacking.

The defunct Sunday tabloid's former editor, Colin Myler, and lawyer, Tom Crone, became the latest to have their names dragged through the mud at the Leveson inquiry into media ethics.

Without naming them, the 81-year-old media baron pointed the finger at the pair for keeping senior executives such as himself, son James and Rebekah Brooks in the dark over the paper's illegal activities.

"There is no question in my mind, maybe even the editor, but certainly beyond, that someone took charge of a cover-up which we were victim to and I regret," he said, before referring later on to a "a clever lawyer".

Crone instantly fired back by accusing Murdoch senior of a "shameful lie", but he was not the only one having his standing brought into question at the inquiry.

The close ties Prime Minister David Cameron shares with past and present News Corp employees and members of the Murdoch family continues to dog him.

Cabinet minister Jeremy Hunt is fighting for his political life following evidence of his office's cosy relationship with News Corp during their failed takeover bid for pay TV company BSkyB.

Hunt was to rule on the bid but it was abandoned following the hacking scandal.

The fallout from the 163 pages of emails between offices saw Hunt's senior aide, Adam Smith, quit his post earlier this week.

Meanwhile former British prime minister Gordon Brown was still seething over revelations from Mr Murdoch on Wednesday regarding a conversation between them in 2009.

The ex-Labour leader was accused of being unbalanced and declaring "war" on News Corp following The Sun's change of political allegiance to the Conservative Party before the 2010 election.

With his inquisitor, Robert Jay QC, baiting Murdoch at times with a much tougher line of questioning on Thursday, the multi-billionaire apologised and antagonised in a candid performance on his second and final day of evidence.

He said "sorry" on 17 occasions for the damage caused by the phone-hacking scandal and delivered some scathing asides about several former employees and rivals in Britain.

He put the failure of his son, James, to pick up the warning signs of the problems at the News of the World down to being "pretty inexperienced", a far from flattering assessment.

Myler and Crone have both disputed former News International chairman James Murdoch's evidence that he was not made aware of the widespread nature of the hacking back in 2008.

Something Crone thought had not escaped Murdoch senior's attention.

"It is perhaps no coincidence," he said following Thursday's evidence.

Rupert Murdoch said he had suffered a "serious blot" on his reputation and that his company had lost hundreds of millions of dollars because of the scandal, the cost included mounting massive internal investigations trying to purge itself of any other illegal activities.

He said it involved trawling through 300 million emails, of which two million received closer scrutiny but insisted the firm found no evidence of wrongdoing in his Australian and US operations.

Murdoch left the inquiry with a smile.

It might be temporary.

If the loss of face and financial pain were not enough, it does not look like it is going to get easier anytime soon for the Murdochs.

A British parliamentary inquiry, which has heard evidence from all the key players in the hacking saga, is set to hand down a much-anticipated report on Tuesday.

And British regulator Ofcom said it was stepping up a probe into whether BSkyB was a "fit and proper" holder of a broadcasting licence.

News Corp holds a 39 per cent stake in BSkyB.

More than 40 people have been arrested over hacking and alleged bribery of public officials by staff at the News of the World and The Sun.

News Corp stuck to the defence of hacking being an isolated problem when the Sunday paper's royal editor and a private investigator were jailed in 2007.

However a fresh police investigation in January last year brought the scale of the practice to light before the scandal exploded in July, when it emerged the newspaper had illegally accessed the mobile phone voicemail messages of murdered British schoolgirl Milly Dowler.

After advertisers boycotted it, the paper was shut within a week with Cameron setting up the Leveson inquiry to probe the ethics of the press and its relations with politicians and police.

The inquiry revealed on Wednesday that Cameron, then opposition leader, made a special stop in 2009 on the Greek island of Santorini to conduct a yacht meeting with Murdoch senior.

By the end of the inquiry, Cameron won't be the only person regretting its existence.