WASHINGTON — The House postponed a vote on a resolution demanding an end to U.S. involvement in Libya amid fears that Democrats and Republicans would unite in backing the measure and handing President Barack Obama an embarrassing foreign policy defeat.

The Republican leadership had scheduled a vote Wednesday on the resolution by Rep. Dennis Kucinich, a Democrat, that "directs the president to remove United States Armed Forces from Libya ... not later than 15 days after the adoption" of the measure. The vote was delayed as the leadership and Obama administration realized frustrated lawmakers likely would support it.

Nearly three months after Obama launched air strikes to back the rebels battling Moammar Gadhafi, Republican and Democratic lawmakers are exasperated with the administration and its inability to spell out a strategy, said one Republican leadership aide, speaking on condition of anonymity to freely describe the situation.

Forces loyal to Gadhafi and the rebels remain in a standoff as NATO and its partners in the military campaign to protect Libyan civilians said Wednesday they have decided to extend their mission for another 90 days

The House Republican plans to hold a special meeting Thursday to weigh Congress' next steps, including the possibility of rescheduling a vote on the resolution.

In a statement, Kucinich said the Republican leadership told him the vote had been delayed to obtain more information and consult with the administration.

"I am disappointed that the president and leadership feel the need to buy even more time to shore up support for the war in Libya," Kucinich said. "It's not surprising that some are now wondering if a preliminary vote count on my resolution came out in favor of defending the (U.S.) Constitution."

Kucinich said Obama violated the Constitution because only Congress has the power to declare war. The lawmaker also said Obama violated the War Powers Act requiring congressional authorization 60 days after the start of military operations.

Obama recently said the U.S. involvement is limited in the NATO-led operation. He also has said he would not send ground forces.