Tony Blair has warned world leaders against letting Saddam Hussein "off the hook".

The prime minister is engaged in an 11th hour bid to overcome international hostility to a war against Iraq.

The move comes as the government brings forward revisions to its draft UN resolution setting a new deadline and new tests for Iraqi disarmament.

"What we are trying to do in the Security Council is to offer very, very clear ideas as to what Iraq has to do in order to demonstrate it is prepared to disarm voluntarily," he said in Downing Street.

"Let us not be under any illusion: there is no way that Iraq will make any concession or co-operate in any way without the threat of force being there."

Downing Street said the prime minister "remains confident" that a second UN Security Council resolution would be passed.

Rebuffing president Jacques Chirac, a spokesman said: "It is for the president of France to choose his words and to decide his country's course."

Amid growing British irritation at France's actions, the spokesman said it was time for the UN to determine whether "it means what it says".

The intervention came as the prime minister faced a growing crisis both on the domestic and international front.

The international development secretary Clare Short was disowned by Labour's high command yesterday after she launched a broadside against the prime minister.

Short kept her job - but is widely tipped to face dismissal unless she jumps before she is pushed.

Speaking last night, the prime minister still hoped that the UN Security Council would support the latest resolution.

Battling against both Cabinet critics and international opposition, the prime minister defended his decision to give Saddam Hussein the deadline of March 17.

In an interview with ITN, Blair said there was enough room in the resolution for Saddam to avoid war.

"We have not given him 10 days to disarm, we have given him 10 days to show he intends fully to co-operate with the inspectors," he said.

"We are in discussion with other countries now. We have laid it down because we believe that gives enough time for him to show that he's fully co-operating," he added.

"I'm working flat out for a second resolution and the important thing at the moment is that we stay together and argue our case collectively and do everything possible to secure that second resolution."

Blair also gave his first official reaction to Short's threat to resign.

"I don't disrespect anyone who has a different point of view. But in the end I have to take a decision. I can't simply make a series of comments on it."

But the new resolution has already been dealt a severe blow with a warning that France and Russia will veto any moves which could lead to war.

In a direct warning to Britain and the US, French president Jacques Chirac took to the airwaves to warn that backing war would set a "dangerous precedent".

The announcement came as UN secretary general Kofi Annan warned that war without a second resolution could be illegal.

Annan stepped into the fray with a serious warning to both Iraq and the US of the consequences that the current crisis would bring.

He warned that if the US decided to act alone the legitimacy of the UN would be seriously impaired.

"The [UN] charter is very clear on the circumstances in which force can be used. If the US and others were to go outside the Council it would not be in conformity with the charter," he said.

The US repeated yesterday repeated its belief that resolution 1441 could be relied upon to mount war.

Russia's foreign minister Igor Ivanov warned it will veto the current US and British resolution that gives Saddam the March 17 deadline to cooperate.

"In the course of the latest session of the UN Security Council, we did not hear serious arguments for the use of force to solve the Iraqi problem," he said.

"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."