President Bush marked five years since ordering the invasion of Iraq by proclaiming yesterday that American troops had achieved “undeniable” success and predicted that the war “will end in victory”.

Osama bin Laden was also planning to commemorate the event, according to an Islamist website. A five-minute audio message attributed to bin Laden was posted on a militant website and was accompanied by a still image of the al-Qaeda leader brandishing an AK47.

It was not clear when the message was recorded or whether it had been timed to coincide with the Iraq anniversary. Last night the authenticity of the voice had yet to be confirmed. Bin Laden was last heard from on November 29, 2007, when he urged European countries to pull their troops out of Afghanistan.

In last night’s recording, he addressed European leaders again as he denounced newspaper cartoons defaming the Prophet Muhammad and attacked the Pope’s alleged role in a “new Crusade” against Islam. “The response will be what you see and not what you hear,” the voice attributed to bib Laden said, without making specific specific threats.

Iraq timeline: five years of conflict

From accusations that the weapons of mass destruction dossier had been sexed-up to withdrawal of British troops from Basra

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• Iraq: five years on

In his speech a few hours earlier, Mr Bush repeatedly linked the Iraq fight to the global battle against al-Qaeda, saying: “The surge has opened the door to a major strategic victory in the broader War on Terror. We are witnessing the first large-scale Arab uprising against Osama bin Laden, his grim ideology and his terror network.”

As Mr Bush spoke, demonstrations were taking place in Washington and elsewhere across the country against a conflict that has cost almost 4,000 American lives and up to $500 billion.

The Democratic presidential candidates Barack Obama and Hillary Clinton repeated pledges yesterday to bring a swift end to the war. Even John McCain, the Republican nominee, who strongly supports the military action, promised a break with the perceived unilateralism of the build-up to the invasion by stating that he would “respect the collective will of our democratic allies” in Europe.

But Mr Bush, in his final months of office, hopes to bind his successor into a strategy that he — and a growing proportion of US voters — believes is beginning to work.

He is resisting pressure from Congress and some senior figures in the Pentagon for further troop withdrawals before the autumn. The recent resignation of the Middle East commander Admiral William Fallon is seen as evidence that Mr Bush is backing General David Petraeus, the military chief in Iraq, who wants to maintain troop levels at about 140,000.

Yesterday Mr Bush said that he did not want to “jeopardise the hard-fought gains” made in the past year since he ordered a “surge” of military power into Iraq.

Mr Obama used a speech near the Fort Bragg military base in North Carolina to present himself as the only presidential candidate offering a clean break with past foreign policy.

He suggested that Mrs Clinton — who voted in the Senate to authorise military action — began opposing the war only when she was “preparing a run for president”.

Mrs Clinton, who met veterans in West Virginia yesterday, has suggested that Mr Obama lacks the experience to be commander-in-chief. But her rival said the way to win the national security debate was “not to compete with John McCain over who has more experience in Washington because that’s a contest he’ll win”.

Mr McCain, who spent this week in the Middle East, arrived in London last night for talks with Gordon Brown and David Cameron today. He said that while progress had been achieved over the past year, “more must be done in coming months to cement the gains made in huge cost in American blood and treasure”.

A senior American defence official told The Times that after the withdrawal of British troops from Basra Palace inside the city last year — and the location of the whole of the British force at the airport northwest of the city — Basra had become “a blind spot”.

“We don’t really know what’s going on inside Basra and that’s not a comfortable feeling,” the official said.

Britain in Iraq

4,100 troops remain in Basra

45,000 servicemen and women involved in invasion

175 deaths in Iraq

109 of those in Basra

£6.5bn projected cost of war by end of this year

US in Iraq

155,000 troops remain in Iraq

3,990 deaths in Iraq

£205bn cost of war to end of 2007

Sources: Ministry of Defence, icasualties.org, Times archives; Congressional Budget Office, icasualties.org, Brookings Institution

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