Rupert Murdoch said today he was sorry he did not close the News of the World years earlier as he claimed that executives at the paper “covered up” the phone-hacking scandal.
He blamed "one or two" senior figures at the now-defunct Sunday tabloid for "taking charge" of hiding evidence of wrong-doing and for misleading him.
But former NOTW legal manager Tom Crone accused Mr Murdoch of a "shameful lie" after the tycoon suggested "a clever lawyer" was behind the cover up.
Finishing his two days of evidence to the Leveson Inquiry into press standards, Mr Murdoch said the hacking scandal would be "a blot on my reputation for the rest of my life".
He admitted that he failed to keep a close enough eye on what was happening at the News of the World, which was closed last July after disclosures that it illegally intercepted murdered schoolgirl Milly Dowler's voicemails.
Mr Murdoch, 81, claimed he was "misinformed" about the scale of hacking at the paper after royal editor Clive Goodman was jailed in January 2007 for listening to royal aides' phone messages.
He said: "I blame one or two people for that, who perhaps I shouldn't name because for all I know they may be arrested yet.
"But there is no question in my mind that maybe even the editor, but certainly behind that, someone took charge of a cover-up which we were victim to and I regret."
He suggested that this attempt to hide the extent of the criminality emanated "from within the News of the World".
He said: "There were one or two very strong characters there who I think had been there many, many years and were friends of the journalists.
"The person I am thinking of was a friend of the journalists, drinking pal, and was a clever lawyer and forbade them to go and see the evidence, or there have been statements reporting that this person forbade people to go and report to Mrs Brooks or James (Murdoch)."
Mr Crone said in a statement after the hearing that Mr Murdoch "could only" be referring to him.
The lawyer went on: "His assertion that I 'took charge of a cover-up' in relation to phone-hacking is a shameful lie.
"The same applies to his assertions that I misinformed senior executives about what was going on and that I forbade people from reporting to Rebekah Brooks or to James Murdoch."
Mr Murdoch said once he knew the extent of the problem at his UK newspapers subsidiary News International, he did everything he could to clean up the company.
"There was no attempt either at my level or several levels below me to cover it up," he said.
"We set up inquiry after inquiry, we employed legal firm after legal firm and perhaps we relied too much on the conclusions of the police."
The billionaire told the Leveson Inquiry his company has spent "hundreds of millions of dollars" investigating activities at all of its newspapers in the wake of the hacking scandal.
Internal investigators have been through 300 million emails and passed anything "faintly suspect" to police, he said.
"We are now a new company, we have new rules, we have new compliance officers, and I think we are showing in The Sun that we can still produce the best newspaper without the bad practices that were disclosed," he said.
Mr Murdoch told the inquiry that in hindsight he should have spoken personally to Goodman when the former royal editor claimed the practice of phone hacking was widespread.
He said: "I should have gone there and thrown all the lawyers out of the place and seen Mr Goodman one-on-one - he had been an employee for a long time - and cross-examined him myself and made up my mind, maybe rightly, maybe wrongly, was he telling the truth.
"And if I had come to the conclusion that he was telling the truth, I would have torn the place apart and we wouldn't be here today.
"But that's hindsight, which of course is a lot easier than foresight."
The media mogul said he "panicked" when he took the decision to close the News of the World but was "glad" he did.
He added: "I am sorry I didn't close it years before and put a Sunday Sun in."
Separately, the inquiry heard that Mr Murdoch has had 67 confirmed meetings with British prime ministers since 1988.
He met Baroness Thatcher seven times, Sir John Major eight times, Tony Blair 31 times, Gordon Brown 17 times and David Cameron four times.
A list of the billionaire's meetings with opposition leaders was also released, showing that he met Mr Blair at least five times and Mr Cameron at least 13 times.
Mr Murdoch today rejected Mr Brown's claim that he was wrong when he said the former prime minister "declared war" on the tycoon's media empire after The Sun switched support to the Conservatives in September 2009.
The Leveson Inquiry, sitting at the Royal Courts of Justice in London, was adjourned until May 9.