Is this war now unstoppable?

113,000 US troops now in Gulf; UK sends 127 aircraft; Blix calls for 'drastic change' from Iraq

Militarily and diplomatically, war on Iraq seems increasingly inevitable, perhaps within a month, barring the most unexpected events in Baghdad.

In a host of developments yesterday, the Pentagon said 113,000 US troops were in the Gulf, on course for the target of 150,000 ­ the accepted minimum for a war ­ by 15 February. An important unit, the 20,000-strong 101st Airborne Division, was ordered to the Gulf.

Geoff Hoon, the British Defence Secretary, told MPs that Britain was quadrupling its air strength in the Gulf to about 100 jets and 27 helicopters, roughly the same as in the 1991 war. Britain has already committed 35,000 troops, including a quarter of its army and its biggest naval task force in 20 years, for a possible conflict.

In Ankara, Turkish MPs permitted Washington to upgrade military bases and ports that could be used in a war on its neighbour. On 18 February it will hold a second vote, which is expected to approve the deployment of US troops. This in effect would allow a second invasion front to bear down on Baghdad from the north.

The timetable is becoming clear. Despite assurances that US forces, with their air power and night-fighting capabilities, could wage war in any season, the Pentagon would vastly prefer to fight in the relative cool of late winter or early spring.

And politically, a war cannot be delayed a year to early 2004. By then the presidential primaries will be in full swing. A war of self-defence is one thing. For George Bush to launch an unprovoked war months before he comes up for re-election is another. It is now or never.

Colin Powell, the US Secretary of State, spelt it out again. "We are reaching the endgame, it is a matter of weeks, not months," he told the Senate Foreign Relations Committee a day after his presentation of Washington's case against Saddam Hussein to the UN Security Council. General Powell brushed off the French proposal ­ backed by Russia and others seeking more time ­ for a big increase in the UN inspection force. "Two or three times as many inspectors would be useful," he said with chilly politeness. But it was up to Iraq to come clean, not for the inspectors to find banned weapons, he said. "If there's a change in attitude [in Baghdad], you don't need to hire more detectives."

The visit to Iraq this weekend by Hans Blix and Mohamed al-Baradei, the chief UN inspectors, amounts to President Saddam's last chance, if he still has one. If they deliver another damning report on 14 February stating that Iraq is still not complying with November's Security Council resolution 1441, then ­ as far as the Bush administration is concerned ­ that's it.

After meeting Tony Blair at No 10, Mr Blix said Iraq needed to show a "drastic change" in its co-operation. More assurances would not suffice; only a huge change of heart.

Meanwhile, America was consulting extensively over whether to offer a second UN resolution that would set Iraq a deadline. But just hours after General Powell had made his UN presentation, Condoleezza Rice, the National Security Adviser, declared: "We clearly don't believe that a second resolution is necessary."

France holds the key, American officials said last night. If President Jacques Chirac signals he will veto a second resolution, then Mr Bush will not seek one, and proceed with his "coalition of the willing" to disarm Iraq. Mr Bush said he would welcome a new resolution "that makes clear the Security Council stands behind its previous demands".

By March, only a coup or a decision by President Saddam to go into exile could prevent a conflict. After months of sabre-rattling, for Mr Bush to call off war in any other circumstances would be hugely difficult.