The controversy over the legality of the war on Iraq looked certain to be reignited last night after it emerged that a former Government lawyer will be called as a witness in a key court case on the conflict.
Elizabeth Wilmshurst, the former deputy legal adviser at the Foreign Office, will be called by Greenpeace as part of its defence of 14 activists arrested for chaining themselves to tanks at a military base.
Ms Wilmshurst, who quit her post on the eve of war because she disagreed with the Attorney General's advice on its legality, has to date refused to talk in detail about her views.
But Tim Owen QC, acting for Greenpeace, told Southampton magistrates' court yesterday that his call for her to give evidence "would not be resisted".
Lodging a defence similar to that of GCHQ whistleblower Katharine Gun, Mr Owen argued that the Greenpeace protesters' actions were necessary to prevent loss of life.
Mr Owen told the court that the "defendants decided they urgently needed to take whatever action they could to prevent a war which was likely to cause thousands of deaths". The "minor disruption" caused by the Greenpeace demonstration was "a last-ditch attempt to bring public attention to the fact that arms that might be used in an unlawful war were being loaded on to tanks".
The Attorney General's own QC was summoned to appear at the court today to defend the legal opinion published on 17 March last year, three days before the invasion of Iraq.
District Judge John Woollard had ruled that it was not within his powers to force the Crown Prosecution Service to disclose the Attorney General's advice to the Government on the legality of war.
But Mr Owen then successfully applied, under section 97 of the Magistrates' Court Act, to summon the Attorney General's legal representative to court to discuss his advice on the conflict.
In a separate move, Robin Cook hit back at Tony Blair's justification for war in Iraq last night by pointing out that the threat of international terrorism had been increased rather than decreased by the invasion.
The former Foreign Secretary and Leader of the Commons said there was a "powerful moral and legal case" against the doctrine of pre-emptive strikes that the Prime Minister outlined last week.
In a speech to St Anthony's College, Oxford, Mr Cook challenged many of the claims made by Mr Blair in his keynote address last week on the war in Iraq.
Mr Cook seized on the Prime Minister's remark that the war was justified because 11 September was a "revelation" that allowed him to "see the threat plainly" from terrorists prepared to combined with rogue states who had developed weapons of mass destruction.
"There are three big problems with this justification for attacking Iraq," Mr Cook said.
"First, there is not a shred of evidence that Saddam had anything to do with 11 September.
"Secondly, everyone sent to Iraq to hunt for weapons of mass destruction cannot find any. And third, there were no international terrorists in Iraq before the war, but there certainly are now."
Mr Cook added that the occupation of Iraq was proving "a massive own goal" for the fight against international terrorism.
"Even Tony Blair in his speech admitted that "the terrorists are pouring into Iraq," he said.
"The brutal truth is that the war on Iraq converted a country that had no link with international terrorism into a country which is rife with international terrorists. This was of course precisely the outcome which our intelligence agencies predicted when they warned that the al-Qa'ida "threat would be heightened by military action against Iraq".
In a Commons debate on the advice, Jack Straw, the Foreign Secretary, said that opponents of the Iraq war should stop arguing about the legality of the action and concentrate on the work of reconstruction.