France, Germany and Russia have said they will not allow the UN to pass a resolution authorising war against Iraq - setting them on a collision course with the US.
Strongest opposition yet to Iraq war
France, Germany and Russia want weapons inspectors in Iraq to be given more time.
Chief weapons inspector Hans Blix said on Wednesday that his teams had been able to interview seven Iraqi scientists in private and that, in the past month, Iraq had been co-operating proactively.
Hastily arranged talks in Paris involving the French, German and Russian foreign ministers took place amid warnings that time is running out for a diplomatic solution to the Iraq crisis.
However the statement by French Foreign Minister Dominique de Villepin did not mention the possible use of veto.
But he told a news conference that France took "exactly the same line as Russia," which has not ruled out using its veto.
Correspondents say the meeting - just days before another key progress report to the UN on Iraqi disarmament - has produced the strongest statement of opposition yet to the proposed second resolution backed by the US, UK and Spain.
However the US and UK have expressed confidence that enough votes would be secured for the resolution.
Also on Wednesday, Turkey's powerful army gave a boost to the US, with public backing for the deployment of US troops ahead of any conflict, despite the lack of authorisation from the country's parliament.
Meanwhile, divisions between Muslim states boiled over at a summit designed to develop a common stance against the war, when a senior aide to Iraqi leader Saddam Hussein accused a Kuwaiti minister of being a "traitor".
The Russian Foreign Minister, Igor Ivanov, also met UK Prime Minister Tony Blair on Wednesday morning.
Mr Blair later told MPs he remained confident there would be backing in the UN for a new resolution demanding that Iraq disarm.
And after the Paris statement, a White House spokesman also said President Bush remained confident of the eventual outcome, and that people should not "jump to conclusions" as consultations were continuing.
Mr Ivanov earlier told the BBC: "Abstaining is not a position Russia can take. We have to take a clear position and we are for a political solution."
"We will not allow a resolution to pass that authorises resorting to force," Mr de Villepin said in Paris.
However neither he nor Mr Ivanov said explicitly that this meant using the veto.
A resolution could be blocked in just two ways - either by veto or by ensuring that it fails to get the required nine "yes" votes of the 15 Security Council members.
The BBC's diplomatic correspondent Barnaby Mason says the Paris statement can be seen as another move in the battle to win the support of the six uncommitted smaller member-states caught in the middle, or as an attempt to persuade the Americans not to put the resolution to a vote at all.
The Security Council splits are likely to come to the fore in public again when chief UN weapons inspector Hans Blix presents his latest report on Iraqi disarmament on Friday.
On Wednesday, Iraq destroyed more elements of its al-Samoud missile system.
But US Defence Secretary Donald Rumsfeld told the BBC he believed Iraq was capable of developing weapons even while inspectors were in the country.
In other developments:
Cardinal Pio Laghi is delivering a message from the Pope to President Bush
Interior ministry troops hold a parade in Baghdad in what the BBC's Middle East correspondent Paul Wood says was "a very definite and concrete show of defiance".
Iran says it is ready to help UN agencies and other aid organisations cope with Iraqi refugees expected to flee a US-led war.