Paul Stephenson, who resigned last July after questions were raised about his links to Murdoch journalists, said police were convinced that a 2006 probe had been thorough enough and had no resources to spare as they fought terrorism threats.

"I think what happened in 2009 is that within the Met we developed a fixed mindset and a defensive mindset around this whole issue," said Stephenson, referring to London's Metropolitan Police, which he headed for two-and-a-half years.

"Fear of taking on a powerful enterprise I do not belive comes into it," he said when asked whether officers were afraid to upset Murdoch's influential publisher News International, the British newspaper arm of his News Corp media empire.

Stephenson was giving evidence to the Leveson Inquiry, a judge-led process that is probing the tangled relationships between Britain's press, politicians and police in the wake of the phone-hacking scandal.

The Guardian newspaper published an article in July 2009 alleging that the practice of phone-hacking stretched to senior figures at the News of the World Sunday tabloid, but police did not reopen the investigation until a year and a half later.

The scandal quickly escalated as police took new account of evidence they had and News International made fresh disclosures, leading Murdoch to drop a multi-billion-dollar bid for British TV company BSkyB and to shut down the News of the World.

Stephenson said he had not read the Guardian article but had heard about it on the radio as he was driving to a conference in the north of England, and had delegated the matter to another senior officer, John Yates.

Yates, who was a friend of former News of the World deputy editor Neil Wallis, decided against reopening the probe after considering the matter for just eight hours. He resigned a day after Stephenson last July.

"I can't in all honesty say I knew the extent of the friendship but I did know he was a friend, yes," Stephenson told the inquiry.

Wallis went on to provide consultancy services for the Metropolitan Police and was also employed to do public relations work for a health spa company at which Stephenson accepted a free extended stay while recovering from illness in 2011.

Stephenson said he had been unaware at the time that Wallis had connections with the spa company, Champneys.

Stephenson also said he had been persuaded that the phone-hacking had been to some extent over-hyped by journalists and others with a political agenda.

POLITICAL PRESSURE

One of those putting forward that viewpoint and urging that the new police investigation Operation Weeting should be scaled back was Kit Malthouse, the deputy mayor of London who has responsibility for the police.

"I don't criticise him for this," said Stephenson. "There was a strong whiff of politics over substance in this matter... that was wrong but it was a widely held view."

London's mayor, Conservative Boris Johnson, will run again for mayor in elections in May against veteran Labour Party left-wing politician Ken Livingstone, who has twice held the leading political role in government before.

Labour member of parliament Chris Bryant, who sits on a parliamentary committee that has been investigating the phone-hacking, called on Monday for Malthouse to resign.

"In any other country this kind of political manipulation would be considered wholly unacceptable and corrupt," he said in a statement.

"It is no longer possible for Londoners to have confidence in the Met with Kit Malthouse sitting at the top table. Kit Malthouse should either resign or Boris Johnson should be forced to sack him."

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