Russia has said it will vote against a draft resolution proposed by the US and UK that gives Iraq a 17 March deadline to disarm.
War could be only days away
It is the first time that Russia has explicitly warned that it will veto the resolution if it is presented to the UN Security Council in its present form.
France, another permanent member, has said it will not let a resolution pass that authorises the automatic use of force, while China has also indicated its opposition to military action at this point.
Russian Foreign Minister Igor Ivanov said the draft resolution was impossible to fulfil and ran counter to the policy currently being implemented under resolution 1441.
"We believe that no new resolution is required at this time, but that it is vital to provide comprehensive support to the IAEA and Unmovic inspectors," Mr Ivanov said.
In an immediate reaction, the White House said it hoped Russia and France would not veto a second UN resolution on Iraq.
"If they were to veto...it would be, from a moral point, more than a disappointment. It would let down millions of people around the world, in this case Iraq, who deserve to be free and have a better life," White House spokesman Ari Fleischer said.
Mr Ivanov's comments came as French Foreign Minister Dominique de Villepin embarked on a tour of the three African members of the Security Council.
Mr de Villepin is trying to win the support of Angola, Cameroon and Guinea ahead of the crucial vote in the Security Council.
After talks in Luanda, Angolan Foreign Minister Joao Bernardo de Miranda, told reporters that Angola was not prepared to commit itself until it came to a Council vote.
Mr de Villepin told the same news conference that a solution to the crisis in Iraq could be found without resorting to the use of force.
His diplomatic push puts him in direct confrontation with the United States and Britain, who are leading efforts to win backing for the resolution.
In other developments:
- Britain's International Development Secretary Clare Short says she will resign if Britain joins an attack on Iraq without UN approval
The head of Iraq's weapons monitoring team, General Hossam Mohammed Amin, says Baghdad will continue to co-operate with the UN disarmament process despite the US and British deadline of 17 March
- A convoy of UN vehicles carrying civilian staff is seen heading south from the Kuwaiti border with Iraq, as non-essential personnel are withdrawn from the area for their own safety
Amid the apparent hardening of the Russian position, our world affairs correspondent Paul Reynolds says the best that Mr Bush and Mr Blair can hope for if there is a veto is to get the so-called "moral majority".
This would be nine of the 15 Security Council votes, but a "moral majority" has no legal status.
As the diplomatic tempo increases, the Pakistani Prime Minister has said his country, a non-permanent member of the Security Council, will not support any military action against Iraq.
Zafarullah Jamali made the statement in the lower house of parliament, which is debating the Iraq crisis.
However, he did not explicitly say whether Islamabad would vote against the second resolution or abstain.
Giving the weapons inspectors more time, as proposed by France and Russia, would "amount to the failed policy of so-called containment," UK Foreign Secretary Jack Straw has said.
Iraq was not being asked to disarm within a week, Mr Straw said in parliament in London.
"But what we are expecting is that the Iraqi regime should demonstrate the full, unconditional, immediate cooperation demanded by successive resolutions since 1991," he said.
To that end, Mr Straw said the UK Government wanted to draw up a list of tasks for Iraq to show it was serious about disarming.
Mr Straw's statement echoes comments by
Prime Minister Tony Blair's official spokesman who said the US and UK would consider a timetable of detailed disarmament moves for Iraq to fulfil by 17 March.
The new benchmarks are likely to be drawn from a document compiled by UN chief weapons inspector Hans Blix which says Iraq has not fully disposed of its chemical and biological weapons arsenal.
The new resolution had been expected to be put to the vote as early as Tuesday, but there are now indications that it may be postponed until later in the week.
US Secretary of State Colin Powell said on Sunday that the probability of war was rapidly increasing and he hinted that hostilities might begin even before the new resolution's proposed 17 March deadline.
As preparations continue, the US and UK have doubled their flights over Iraq's no-fly zones to as many as about 500 sorties a night and extended the number of targets hit.