Nato hit one of the worst storms in its 54-year history yesterday after France, Germany and Belgium blocked military planning for steps to defend Turkey in the event of a US-led war against its neighbour Iraq.
The alliance failed to break the deadlock at two meetings of its North Atlantic Council yesterday, and Secretary-General George Robertson said it would hold a further session at 1000 GMT today.
The United States accused the three European countries of plunging the 19-nation alliance into a credibility crisis, but US Secretary of Defence Donald Rumsfeld said the dispute was no threat to its long-term survival.
Their move prompted Turkey, nervous about possible counter-attacks from Iraq, to seek consultations for the defence of its territory during an emotionally charged meeting of the Council.
Robertson told a news conference after yesterday's second meeting that alliance ambassadors had received an account of the potential military threat facing Turkey by the chairman of Nato's military committee, General Harald Kujat.
The presentation showed Turkey's concerns were legitimate and the threat real, Robertson said.
"I think it was pretty sobering advice that they got... and it may well affect the way they think about this issue when the morning comes," he added.
Germany and France have led European resistance to US plans to use force, without UN approval if it believes it necessary, to ensure Iraq holds no weapons of mass destruction.
Backed by Belgium, they argue making preparations for a possible conflict could suggest they had given up on diplomatic efforts at the United Nations to avert war.
French diplomats sought to play the drama down, saying there had been worse bust-ups during the alliance's history. But one Nato source said only the row over US Pershing cruise missile deployment in Europe in the 1980s was more serious.
Diplomats said the three countries came under heavy fire in the morning meeting, with one ambassador charging "You are doing grave damage to the alliance". Another ambassador told Germany it had been protected from Soviet threats through the Cold War but was not prepared to help another ally now.
Rumsfeld told eight European newspapers yesterday the blocking manoeuvre was "a disgrace" and US ambassador to Nato Nicholas Burns said that "because of their actions, Nato is now facing a crisis of credibility".
But Rumsfeld sounded a calmer note at a Pentagon briefing later, saying Turkey would be provided with protection outside of Nato if necessary.
"There's three countries. There are 19 countries in Nato. So it's 16-3," he said. "I think it's a mistake, and what we have to do for the United States is make sure that that planning does go forward, preferably within Nato but if not bilaterally or multiple bilaterals."
Britain, Washington's closest ally, said it was disappointed but at least discussions were continuing.
Poland, a relative newcomer to the alliance, said the three countries' manoeuvre was a badly-timed publicity stunt which would play into the hands of Iraqi President Saddam Hussein.
The Nato article invoked by Turkey says "parties will consult together whenever, in the opinion of any of them, the territorial integrity, political independence or security of any of the parties is threatened".
Turkey is a likely northern launchpad for any US-led war. Ankara took its step after France and Belgium, breaking what is known as a "silence procedure", voiced objections to proposals to start defence planning shortly before a 0900 GMT deadline. Germany's objection came in around the deadline.
Belgian Foreign Minister Louis Michel, speaking on French radio Europe 1, said that going along with planning proposals now would imply acceptance of a "logic of war".
"And right now it has to be said that chances of resolving the conflict peacefully are taking off," he said.
Struck said on Sunday Berlin and Paris wanted UN troops to bolster weapons inspections in Iraq and would outline the plan when top inspectors Hans Blix and Mohamed ElBaradei issue a new report to the Security Council on Friday.
The deadlock over the Turkey defence issue appeared to have put another dent in Nato's already battered credibility.
"If allies can't respond to Article IV it introduces doubt about whether Nato can fulfil its commitments," one Nato diplomat said. "If they can't agree something so small could they ever agree on something bigger?"