The House of Representatives on Thursday turned back an effort to prohibit funds for the U.S. military operation against Libya, a win for President Obama in the ongoing constitutional showdown with Congress over war powers.

The vote was 229-199 against the measure that would have barred funds for U.S. participation in the NATO-led mission against Muammar Qaddafi's forces.

Lawmakers argue that Obama violated the 1973 War Powers Resolution that requires a president to seek congressional approval within 60 days of the first military strikes, a move the commander in chief did not make. Instead, Obama informed Congress last month that such assent was unnecessary because the limited U.S. role does not rise to full-blown hostilities.

Incensed House Republicans and Democrats voted overwhelmingly last month to deny Obama the authority to continue the mission, a largely symbolic vote that was still a rebuke to the president. But they stopped short of cutting off funds for the operation, muddling the message from the House.

The signal from the House Thursday also was less clear as lawmakers voted for a measure barring the Pentagon from providing "military equipment, training or advice or other support for military activities," to an outside group, such as rebel forces, for military action in or against Libya. The vote was 225-201.

The intent of the measure is to prohibit aid to the rebels such as weapons and assistance to the Transitional National Council including operational planning. The broad effort also would target contractors in Libya.

"Congress has allowed the president to overreach in Libya," said Rep. Tom Cole, the Republican sponsor of the amendment. "We should not be engaged in military action of this level unless it is authorized and funded by Congress."

The votes Thursday ratcheted up the pressure on the administration as Libya remained a stalemate between Qaddafi and rebel forces, and war-weary NATO allies signaled their patience was wearing thin. Italy announced that it was reducing its participation in NATO's campaign by removing an aircraft carrier from the region and pulling thousands of troops home.

Calling the conflict "illegal and unauthorized," Cole said Libya "did not attack us, did not attack NATO ... quite simply, however much we detest Mr. Qaddafi and his regime, we have no reason to be at war."

Rep. Justin Amash, the Republican co-sponsor of the failed measure, said the House had an "opportunity to stop this unconstitutional war against Libya."

Opponents, such as Rep. Norm Dicks, a Democrat, argued that the United States should be allowed to continue the mission along with its NATO allies. He reminded Republicans that former President Ronald Reagan had challenged Qaddafi, and the U.S. should finish the job.

The House considered the amendments as part of a $649 billion defense spending bill that would not go into effect until Oct. 1. The defense bill includes no funds for the Libyan operation -- the Pentagon has said it could cover the expense with existing funds -- but the measures would effectively bar funds for the mission.

Last month, the White House put the cost of U.S. military operations in Libya at about $715 million, with the total increasing to $1.1 billion by early September.

Since NATO took command of the Libya operation in early April, the U.S. role has largely been limited to support efforts such as intelligence, surveillance and electronic warfare. The U.S. has launched airstrikes and drone attacks, flying more than 3,400 sorties.

The Senate has delayed consideration of a resolution to authorize the U.S. mission in Libya.

Earlier Thursday, the House rejected several amendments that would have accelerated the withdrawal of U.S. forces from Afghanistan as Republicans and Democrats argued that the nation cannot afford a conflict now in its 10th year.

Obama has ordered a reduction in the force of 10,000 by year's end, with 23,000 troops to be withdrawn by September 2012.

About 100,000 U.S. troops are in Afghanistan as part of an international coalition.

The House was intent on completing the defense bill by week's end. The overall measure is $9 billion less than Obama sought but $17 billion more than current levels.

The administration has threatened a veto if the legislation is unchanged, citing provisions limiting the president's authority to transfer terror suspects from the U.S. naval facility at Guantanamo Bay, Cuba, and a prohibition on increasing enrollment fees for health care for military retirees.

"If a bill is presented to the president that undermines his ability as commander in chief or includes ideological or political policy riders, the president's senior advisers would recommend a veto," the administration said in a statement last month.

The Senate still must produce its version of the bill, and then reconcile it with the House measure.