The Government gave no reaction last night to Mr Colin Powell's UN statement on Iraq, saying it had to study it before commenting.
Fine Gael, however, warned against unilateral action by the United States without a fresh UN mandate. Labour and the Green Party suggested the information provided by Mr Powell was not enough to justify military action, and called for the UN inspectors in Iraq to be given more time.
A Government spokeswoman said the Minister for Foreign Affairs, Mr Cowen, would be discussing the US Secretary of State's submission with Ireland's Permanent Representative at the UN before giving a response.
Fine Gael's foreign affairs spokesman, Mr Gay Mitchell, said unilateral action would not comply with the rules of international law. "If the US can persuade the Security Council, or if the UN inspectors' report convinces the Security Council, the rule of international law can be applied."
Mr Mitchell said his party was seeking a Dáil debate on the issue next week together with a question-and-answer session with the Minister for Foreign Affairs on the Government attitude.
Labour's foreign affairs spokesman, Mr Michael D. Higgins, said the material presented by Mr Powell should be made available to the UN inspectors in Iraq "so that its action can be tested. Indeed one wonders why, if this information has been with the United States for some time, it has not been presented in public before or provided to the inspectors before this.
"Mr Powell's presentation shows the merit of asking those with the intelligence capacity to monitor weapons of mass destruction to share it with the United Nations to begin a process of disarmament in the region and globally, particularly in relation to biological and chemical weapons."
The Green Party chairman, Mr John Gormley, said Mr Powell's statement had provided "flimsy" evidence and fell far short of what was required to justify a war.
"To justify a war on this flimsy evidence is inexcusable," he said. "The presentation by Mr Powell to the UN was slick and dramatic but was based mostly on assertion. His statement begs the question: if the US has had such damning information in its possession why has it not passed this on to the arms inspectors for verification?
"This was a last-ditch effort by the US to secure a UN resolution. Unfortunately, such is the might of the US they may well succeed in their goal. However, a cobbled-together UN resolution based on such propaganda would undermine the credibility of the organisation. It is quite clear at this stage that the French are ready to capitulate to American interests. There can be no doubt that world governments are out of touch with world opinion on this matter."
Mr Gormley welcomed the rerouting of 17 US troop-carrying planes to Frankfurt from Shannon. "Obviously this is only a small step in the right direction. Our ultimate aim is that no US troops will land in Shannon as part of the American war effort against Iraq."
Meanwhile, the Sinn Féin leader in the Dáil, Mr Caoimhghín Ó Caoláin, will lead a party delegation to the US and British embassies today to hand in letters urging those governments to "show some restraint" and to give the UN inspectors more time.