It would be an "unwarranted shift of power" for the courts to make pronouncements on the Government's right to go to war, three of the country's top judges were told yesterday.
This was the Prime Minister's response to a bid by the families of British soldiers killed in Iraq to force him to hold a public inquiry into why Britain entered the conflict.
The bereaved relatives, including a mother from Staffordshire, want Tony Blair "to be held accountable" if there was no legal basis for the conflict and its aftermath.
Their legal battle for a judicial review of the decision not to hold a further public inquiry was blocked by Mr Justice Collins in the High Court.
But yesterday the families went to the Court of Appeal to ask Master of the Rolls Sir Anthony Clarke, the President of the Queen's Bench division of the High Court Lord Justice Judge, and Lord Justice Dyson to overrule the High Court decision.
Rabinder Singh QC, representing relatives of four soldiers who lost their lives in Iraq, had told the judges that the Government could be guilty of a violation of the men's right to life under the Human Rights Act.
But Philip Sales, who represents the defendants in the case - the Prime Minister, the Attorney General and the Defence Secretary - attacked the claim, which could lead to a declaration that the military action was unlawful.
He said: "The nature of the application is a naked appeal to the courts to hold that they have the right to order a further inquiry into the legality of a military conflict."
But it was "inconceivable" that, by incorporating the right to life into the Human Rights Act, the State also agreed there was a legal obligation, which the courts could enforce, over the reasons for military action.
If the claimants were right, then the State would be under such an obligation every time a soldier was killed or put at risk of being killed, he told the judges.
"That would represent a major, and the defendants submit, an unwarranted, shift of power to the courts in the very areas where for sound constitutional reasons they have exercised extreme caution about becoming involved: the disposition and use of armed forces and the conduct of international relations."
Rose Gentle, Peter Brierley, Beverley Clarke and Susan Smith, who lives in Tamworth, are all close relatives of British servicemen killed whilst on active duty in Iraq between March 20, 2003 and June 28, 2004.
They lost loved ones in roadside bombs, a road traffic accident, helicopter collision and friendly fire.
Mrs Smith's son Private Phillip Hewitt, a member of the 1st Battalion Staffordshire Regiment, was killed by a roadside bomb.
The relatives believe the decision to go to war because Iraq possessed weapons of mass destruction was "based on a series of lies" and was "an illegal act".
They tried to persuade the Government to hold a further public inquiry, but were rebuffed.
The families want the courts to declare that the Government's refusal to hold an inquiry violates the "right to life" guaranteed under Article 2 of the European Convention on Human Rights.
The judges reserved their decision on whether to hold an inquiry to a later date.