By Susan Cornwell and Caren Bohan

WASHINGTON (Reuters) - U.S. President George W. Bush asked Congress on Monday for $189.3 billion (93.2 billion pounds) to fund the wars in Iraq and Afghanistan, another huge request that faced deep scepticism from lawmakers opposed to prolonging the Iraq conflict.

Bush's request covers military operations for fiscal 2008, which began on October 1, the White House said. If approved it would make 2008 the most expensive year in the Iraq and Afghan wars and would be on top of about $600 billion already approved for those conflicts.

House of Representatives appropriators said earlier this month they would not even consider the new war funding request until early 2008, and that they wanted to link it to a plan to bring U.S. combat troops home.

But they left open the possibility of paying for the war through an interim measure called a "bridge fund."

In announcing the latest war request, Bush prodded Congress to approve the request swiftly and unconditionally.

"They should pass a good, clean bill as soon as possible," Bush told reporters at an event where he was flanked by veterans and family members of fallen soldiers. Lawmakers who say they support the troops should "show it," he said.

"Congress should not go home for the holidays while our troops are still waiting for the funds they need," Bush said.

"Isn't this getting to be a little old?" Senate Majority Leader Harry Reid, a Democratic war opponent from Nevada, asked on the Senate floor after Bush spoke.