Watch Out

“I can only say I had no knowledge," he told BBC Radio 4’s Today programme.

"As far as I am aware, no ministers had any knowledge.”

Mr Woolas repeatedly stressed that the arrest had been for “conspiracy” to commit misconduct in a public office.

“The wise thing to do for everyone, especially commentators, is to wait and see what is happening.”

Senior Tory sources have branded the operation “Stalinesque”, and suggested police must have received authorisation from the very top of the Government.

Boris Johnson, the Mayor of London, said that he had been informed of police plans in advance and voiced “grave” concerns to the acting Met Commissioner, Sir Paul Stephenson, warning him that he did not regard it as “commonsense policing”.

Only yesterday Mr Johnson was the target of an extraordinary verbal attack by the outgoing Commissioner, Sir Ian Blair, whom he forced from office. Sources close to the Shadow Cabinet suggested that the timing could not have been coincidental and said the decision to arrest such a senior politician would have been cleared "at the very top".

Among those speaking up on Mr Green's arrest was Mr Davis, who quit the Tory front bench to campaign against the Government’s erosion of civil liberties and said that it was “somewhere between an astonishing error in judgment through to judicial intimidation”.

Mr Davis said Mr Green had only been “doing his job”. He told BBC Radio 4’s Today programme: “None of this put in any way national intelligence, national security, or international relations at risk - yet we end up with a situation that is in some way reminiscent of Robert Mugabe’s Zimbabwe, with an Opposition spokesman being arrested for nine hours. It is extraordinary, frankly.”

Mr Davis said he found it “hard to believe” that ministers were not told that Mr Green was about to be arrested. "I cannot believe it,” Mr Davis said. “Why were they not told?”

Chris Huhne, the Liberal Democrat home affairs spokesman, described the move as “the most worrying development for many years”.

“Receiving information from government departments in the public interest and publicising it is a key part of any MP’s role,” he said. “This is the most worrying development for many years, with the potential to shift power even more conclusively from Parliament to the Government. It is also extraordinary considering Gordon Brown himself as Shadow Chancellor received and publicised many leaked official documents.”

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