Labour believes Opposition is to blame for leaks

Ministers are braced for more damaging leaks this weekend as they pointed the finger at the Conservatives for the disclosure of the Attorney General's secret advice to Tony Blair on Iraq.

Ministers are braced for more damaging leaks this weekend as they pointed the finger at the Conservatives for the disclosure of the Attorney General's secret advice to Tony Blair on Iraq.

Senior figures in Labour's campaign headquarters suspect the Tories may have been the source of one of the most damaging leaks in modern times during a general election. A key Labour strategist said: "It was carefully orchestrated to make sure it did the maximum damage." Labour officials believe the incremental way in which the leaks were made showed they were carefully planned by someone with "media savvy", who was ready to leak more of the report until the Government published it in full.

Possible sources for the leak are few. The circulation of the report was so tightly controlled inside No 10 that most cabinet ministers had not read it until it was leaked. Patricia Hewitt, the Secretary of State for Trade and Industry, said she read it this week on a website.

Outside Mr Blair and his closely-knit team, other possible sources, according to Labour officials, include someone connected to the Butler inquiry, which had a small secretariat at Whitehall. The team consisted of the respected public servants Lord Butler; Sir John Chilcot, chairman of the Police Federation; Ann Taylor, a former Labour chief whip; Michael Mates, a widely respected senior Tory MP; and Field Marshal Lord Inge.

Lord Goldsmith refused to give his report to them but relented when Lord Butler threatened to abandon the inquiry. Labour admits that it could have come from a disgruntled civil servant but says this is unlikely. The legal department at the Foreign Office was strongly opposed to the Attorney General's final conclusion that the war was legal, and Elizabeth Wilmshurst resigned in protest as deputy legal adviser, although there is no suggestion she was responsible for the leaks.

Fears among Labour officials that the Tories coordinated the leaks as part of an election strategy were dismissed as "paranoid" by a Tory spokesman.

For their part, one theory that has been raised within the Tory campaign team is that the leaks came from Downing Street to allow the Iraq issue to burn itself out more quickly.

Lord Ancram, the Conservative deputy leader, refused to deny the Tories were behind the leak when challenged by The Independent. He said he had no idea where the leak came from.

The Labour strategy team fears there could be further attempts to destabilise its campaign.An obvious target could be the minutes of the cabinet meeting in July 2002, chaired by Mr Blair, when it is understood he first ordered the Attorney General to prepare advice on the legality of joining the US in an invasion of Iraq. The Foreign Secretary, Jack Straw, is said to have questioned the need for an invasion after MI6 reported the US was trawling for intelligence to back up its case for regime change in Iraq.

The leaks began last weekend when an outline of Lord Goldsmith's findings was read to a journalist at the Mail on Sunday. With the controversy raging, copies of Lord Goldsmith's conclusions were leaked. They were handwritten to avoid being traced, and sent toChannel 4 News, the BBC and The Guardian.

Meanwhile, Sir Andrew Turnbull, the Cabinet Secretary, was facing allegations last night that he breached civil service rules by failing to circulate the Attorney General's advice.

Clare Short, who resigned over the war, will make a complaint after the election, under the ministerial code which requires legal advice from law officers to be circulated to ministers in full.

Tories also accuse Sir Andrew of being economical with the truth. He was asked on 10 March this year by the Public Administration Committee whether there "was a complete text that existed at that time [17 March 2003] that they could have seen if it had been made available to them". He replied that "there is not a longer version of that advice".

Mr Ancram said: "We now know that that was not the case. Why did Sir Andrew Turnbull say it?"