There appeared to be little common ground between countries led by Britain, which is set to present the resolution with the US, and anti-war giants France and Germany.
British Foreign Secretary Jack Straw confirmed that the new resolution would likely be presented to the UN Security Council early this week, aiming for a decision on it within about two weeks.
"We are now approaching the end of the final opportunity that Saddam Hussein was given," in UN Security Council resolution last November, he told reporters.
EU leaders last week agreed a surprisingly tough-worded joint statement on Iraq, warning that UN inspections cannot go on forever and admitting that force could be used as a last resort.
But the statement, hammered out at an emergency summit in Brussels, is struggling to paper over the clear gulf which remains within the 15-member bloc.
France in particular remains firmly opposed to the plan for a new UN resolution.
"A new resolution is neither useful nor necessary. The use of force can only be the last resort," said French President Jacques Chirac's spokeswoman Catherine Colonna Monday.
Colonna said that France was set to make new proposals to reinforce measures already in place to disarm Iraq. The plans would be unveiled at the United Nations on Monday she said.
"France wants to give disarmament in Iraq through peaceful means every chance of succeeding, through inspections that should be pursued and reinforced," she told reporters.
German Foreign Minister Joschka Fischer also reiterated Berlin's call for UN weapons inspectors to be given more time.
"Inspectors should be given the time they need," he said, while also referring to a letter sent by chief UN weapons inspector to Iraq ordering the destruction of Iraqi missiles.
"That is the only way to implement the relevant resolutions, without falling into the automatic path of war," he said.
Straw underlined the need for international unity over Iraq, but said debate at the UN could not go on indefinitely.
"As we want an international consensus and we want the cooperation of Iraq fully and completely to comply in substance as well as process, we'll be allowing a good period of up to two weeks, maybe a little more, before we ask for a decision," he said.
Spanish Foreign Minister Ana Palacio also confirmed Monday that Madrid will help draw up a new resolution. "Spain will be a co-author of the resolution. We are in the process of negotiating," she said.
US President George W. Bush met Spanish Prime Minister Jose Maria Aznar on his Texas ranch at the weekend and said afterwards that the Security Council had less than two months to prove its mettle by passing a resolution, to be unveiled this week.
Meanwhile Belgian Foreign Minister Louis Michel expressed support for a French threat to veto a second UN resolution which could give the green light for war on Iraq.
Asked whether he would back a French veto, he replied: "I'll support all the initiatives that can lead to peace." Arab League head Amr Mussa meanwhile said that the European Union and Arab countries must work together to "avoid war" in Iraq while ensuring that Baghdad meets its UN obligations.
"You can never belittle the consequences of any war, especially in an area like the Middle East already frustated by the Israeli occupation and the bias towards Israel," he said.
Mussa was invited by the Greek EU presidency to attend the regular monthly meeting of EU foreign ministers, dominated by the latest developments in the Iraq crisis - Sapa-AFP.