Tony Blair could be brought back before the Iraq war inquiry to face questions over whether he pressurised his Attorney General to change his advice and declare the invasion to be legal.
As it emerged that a period of time has been set aside in the autumn to recall witnesses, MPs last night called for the former Prime Minister to be brought back for a second cross-examination by Sir John Chilcot's panel.
Previously classified memos released this week to the inquiry hinted that the former Attorney General, Lord Goldsmith, faced political pressure to reverse his opinion on the war's lawfulness.
One document disclosed that the day before Mr Blair met President George Bush to discuss the Iraq crisis – a meeting at which Mr Blair backed the invasion in principle – Lord Goldsmith warned that military action would be illegal without a second United Nations resolution. Mr Blair complained in the margin of the memo: "I just do not understand this."
Lord Goldsmith was to reverse his legal advice shortly afterwards.
Mr Blair told the Chilcot inquiry five months ago that he had reached the view at the time of the Bush meeting that it would have sent a "very bad signal" to the world if the US-led coalition had backed off from conflict with Saddam Hussein when he was "playing around" with UN weapons inspectors.
However, he maintained he would not have gone to war if Lord Goldsmith had concluded it was illegal.
Although the material published this week had already been received by the Chilcot panel, its members were constrained from asking Mr Blair about it because it was classified at the time.
Sir John's team is due to complete its current round of hearings this month, with a view to reporting within around six months' time.
MPs last night said that Mr Blair should be the first of the witnesses to be re-examined. Jeremy Corbyn, the Labour MP for Islington North, said: "This new evidence is highly significant. I would hope and assume that the inquiry would recall the former Prime Minister to answer for this.
"He always maintained in parliament and public that the war was legal. The inquiry needs to go through the contents of these memos with him."
Sir Menzies Campbell, the former Liberal Democrat leader, said: "These letters are confirmation of conclusions that had already been reached – either by inference or from other documents which have been previously leaked.
"It's clear the Attorney General's view went through a 180 degree turn while he was in the United States."
But he added: "I suspect that to recall Tony Blair or Lord Goldsmith would not add much to our understanding of these events."
Witnesses that will appear later this month include Hans Blix, the former UN weapons inspector; Bob Ainsworth, the former Defence Secretary; and John Prescott, the former Deputy Prime Minister.
The five-strong panel says it intends to produce its final conclusions "around the turn of the year".
Questions that can be asked
Sir John Chilcot expressed his frustration in January that he was unable to refer to the relevant documents while questioning Lord Goldsmith, the former Attorney General, about why he gave the "green light" for the war because the documents were classified.
The former Attorney General can now be asked, with the papers declassified, why he changed his mind and stated the invasion was justified, when his previous legal advice, and confidential letters to Tony Blair had said that war without a fresh security council resolution would be illegal. He can be asked why he executed a U-turn without giving evidence of any new legal evidence to justify the change of mind.Reuse content