President Bush yesterday asked Congress for another multibillion-dollar slice of military funding, spending which should ensure the cost of the Iraq war rises over the $500 billion mark early in the new year.

His request for an additional $42 billion brings the total budget for Iraq and Afghanistan wars in the financial year beginning this month to $190 billion. Spending has risen from $8 billion a month last year to a projected $15 billion.

At least four-fifths of the new allocation will go towards the battles in Iraq, for which the US taxpayer has already footed a bill conservatively estimated at $462 billion.

Anita Dancs, the research director at the National Priorities Project, said: “Each year of this war is becoming more and more expensive, draining money available for other needs. For instance, the sums we are spending on Iraq this year would have been enough to provide healthcare for the 44 million Americans without insurance coverage.”

Before the war began in 2003, Mr Bush’s officials confidently predicted that the conflict would cost about $50 billion. Lawrence Lindsey lost his job as a White House economic adviser after suggesting spending might reach $200 billion.

Some of Mr Bush’s latest spending request is allocated for the State Department’s diplomatic missions in the Middle East, but the bulk of it will used to support military operations.

It includes around $11 billion for purchasing 7,000 more Mine Resistant Ambush Protected (MRAP) vehicles, on top of the 8,000 already funded.

Such equipment is regarded as urgently needed to protect US troops from deadly roadside bombs which have accounted for many of the 3,830 American servicemen killed in Iraq.

It is also estimated that at least 73,000 Iraqi civilians have died in the war since the US-British invasion in 2003.

The Democratic-dominated Congress has delayed approving Mr Bush’s war spending for the coming year, after failing to attach a binding timetable for the withdrawal of troops to the previous budget.

House of Representatives leaders have indicated they will provide interim funding while preparing for a new fight over the direction of the war after Christmas.

White House deputy press secretary Tony Fratto said Mr Bush hopes that congressmen who say they want to support US soldiers will act quickly.

The funding call came as al-Qaeda leader Osama bin Laden called on insurgents in Iraq to bury their rivalries and unite against the US-led coalition, in an audiotape broadcast on the Arabic station al-Jazeera.

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