UNITED NATIONS, Aug 30: The United States is finding it difficult to solicit troops from other nations to support its military operations in Iraq, as the costs of war kept increasing to a staggering one billion dollars a week and mounting US casualties.

The Bush administration is reluctant to put the post- occupation operations under the UN umbrella, even though UN Secretary General Kofi Annan has suggested that any such operation authorized by the Security Council could be led by American commanders on the ground.

Many US lawmakers, alarmed at the costs of war and its aftermath, are calling for a UN mandate to help US financially and with more troops, but the Bush administration believes that it can attract peacekeeping troops for Iraq from at least Pakistan, India and Turkey by placing the operation under the UN flag.

Senator Joseph Biden, a senior democrat, who is considering a shot at the presidency in next year’s elections, told newspapers “the costs are staggering, the number of troops are staggering, we’re seeing continuing escalation of American casualties, and we need to turn to the UN for help, for a UN-sanctioned military operation that is under US command”.

“We’re 95 per cent of the deaths, 95 per cent of the costs, and more than 90 per cent of the troops,” Mr Biden added.

Since May 1, when President Bush announced an end to major hostilities, 144 US soldiers have died. That’s six more than those killed during the invasion itself.

Currently, 138,000 US troops are in Iraq, and Britain and 26 other countries have contributed about 23,000.

At the UN, Russia and France are pressing for an international force under a broad UN mandate to help the occupation forces.

French President Jacques Chirac said in Paris on Friday that the United States should transfer political power to the Iraqi people immediately. Only the United Nations, he said, “is fit to provide its legitimacy”.

But France, Russia and other European governments want greater share in the reconstructing process in Iraq, including some of the lucrative contracts American firms have obtained.