Sir Ian Blair appeared to have saved his career tonight after securing support from the Home Secretary, the Prime Minister and the Metropolitan Police Authority over his secret recording of six private telephone conversations.

But the Commissioner of the Metropolitan Police was accused of behaving in a "wholly unacceptable" manner by taping the calls with public figures, including the Attorney General and the chairman of the Independent Police Complaints Commission (IPCC).

Len Duvall, chairman of the Metropolitan Police Authority (MPA), described a "robust" conversation with Sir Ian but made it clear that he did not believe this was a matter for resignation.

He said "It is totally unacceptable. We do not expect it to occur again. There were six calls, that is six too many. The Commissioner accepts this and has given me an assurance this will never happen again."

Lord Goldsmith, the Attorney-General, said that he accepted Sir Ian's explanation and apology, and considered the matter closed.

Scotland Yard today revealed that Sir Ian had made the recordings, without telling the public figure at the other end of the line, because: "He thought that they would be discussing a complex issue and as he was without a note-taker it would be helpful to have a record of the conversation."

After his meeting with senior officers, Mr Duvall gave more details of the six calls, three of which were made to representatives of the IPCC, Nick Hardwick and Roy Clark, on July 22 and one with John Wadham, its chairman, three weeks later.

He added: "A fourth call was with the Attorney General on 8 September 2005 to whom the Commissioner apologised and explained why this happened. This apology has been accepted by the Attorney General who now considers the matter closed.

"At the conclusion of the call to the Attorney General Sir Ian immediately made a call to a member of his family and as the machine did not disconnect this fifth call was also accidentally recorded.

"The sixth call was to Ian Katz of the Guardian on 26 January 2006 with whom the Commissioner had been giving a series of face to face recorded interviews over the past year. Due to timescales and availability this final interview took place over the telephone and was therefore also recorded, as is normal practice for interviews with journalists.

"We understand that there are no further tape recordings by Sir Ian and these were the only calls that have been recorded."

As ministers closed ranks in support of Sir Ian, Tony Blair's official spokesman said that Sir Ian had the Prime Minister's "full confidence".

Charles Clarke, the Home Secretary, later announced that Sir Ian had his full support, adding: "I continue to have full confidence in Sir Ian."

The Met Chief was also supported by Ken Livingstone, the London Mayor, who said: "I want to give my full backing to Sir Ian Blair, who is doing a first-class job in delivering neighbourhood policing to every part of London, raising the visibility of the Met and driving down the fear of crime."

Sir Ian, 52, took over as the Metropolitan Police Commissioner last February and is in charge of 30,000 officers.

He has been dogged by controversy since taking over. An investigation is ongoing into his handling of the shooting of Jean Charles de Menezes, a Brazilian electrician suspected, 24 hours after the July 21 terrorist bombings in London. He has won few friends in the media, and in one speech directly accused newspapers of racism.

Nick Clegg, the Liberal Democrat home affairs spokesman, said today: "Controversy appears to attach itself to Sir Ian on an almost daily basis. These reports raise serious questions about his judgment and his leadership style - Sir Ian will have to come up with a very good explanation for this extraordinary behaviour."

Shami Chakrabarti, director of human rights group Liberty, went further in condemning Sir Ian’s actions. "I think that his behaviour appears to be unconstitutional, unethical, quite possibly unlawful," she told the BBC Radio 4 Today programme.

"The bitter irony of this is that is a government that has made great play of its support for the police. In my view it's given them too many unchecked powers and here it is on the receiving end of this most appalling abuse of police power."

The existence of the taped conversations came to light as part of the IPCC inquiry into the shooting of Mr de Menezes at Stockwell Tube station.

Under the Regulation of Investigatory Powers Act 2000 (RIPA), it is not illegal for individuals to tape conversations, provided the recording is for their own use. Recording or monitoring are only prohibited where some of the contents of the communication are made available to a third party.

If a person intends to make the conversation available to a third party, they must obtain the consent of the person being recorded. Under RIPA it is a civil, not criminal, matter if a conversation or eemail has been recorded and shared unlawfully.

Mr de Menezes, 27, was shot seven times in the head by plain clothes police officers at Stockwell Tube station on July 22, the day after the alleged attempted suicide bombings in London.

Hours later, Sir Ian said during a press conference that the shooting was "directly linked" to anti-terror operations and praised the force for "playing out of its socks".

The next day, Scotland Yard admitted the victim was not connected to the attempted bombings and was an innocent victim.

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