WASHINGTON -- The United States turned up the pressure on quarreling NATO allies to take command of the air war in Libya on Wednesday, suggesting the U.S. could step away from its leadership role as soon as this weekend, even with the conflict's outcome in doubt.
In Congress, meanwhile, the Republican speaker of the House demanded that President Barack Obama quickly spell out the nation's precise goals in Libya. White House officials said Obama would keep updating the American people and a formal address was possible. Secretary of State Hillary Rodham Clinton said order could be resolved quickly – if Libyan leader Moammar Gadhafi would just quit.
The U.S. threat to give up its leadership of the military efforts rang somewhat hollow, since officials said there was no absolute deadline to hand over frontline control to other countries, or for an end to all U.S. participation. Still, the administration is eager to hand off the lead role in a conflict that some of Obama's closest advisers resisted and that is raising complaints in Congress.
Defense Secretary Robert Gates, himself an early skeptic American military intervention in Libya, said Obama made clear from the start of the international air campaign last Saturday that the U.S. would run it for only about a week. The assault began with a barrage of U.S. cruise missiles fired by ships and submarines in the Mediterranean and with American Stealth bomber flights – the first war initiated by a president who inherited two others.
In an exchange with reporters traveling with him in Cairo on Wednesday, Gates was asked whether his comments meant the U.S. had set a hard deadline of this Saturday for turning over command of the air operations.
"I don't want to be pinned down that closely," he replied. "But what we've been saying is that we would expect this transition to the coalition, to a different command and control arrangement, to take place within a few days and I would still stand by that."
The U.S. and its partners are struggling to overcome a key dilemma of their mission: how to halt Gadhafi's ground forces, which are now attacking urban areas, without endangering the very civilians the allies are supposed to protect.
As Obama returned to Washington from a three-nation tour of Latin America, Democrats lined up in support of his Libya approach. Congressional liberals and conservatives have criticized the president – some accusing him of acting too slowly, others saying he moved too quickly. Some have said he should have asked for Congress' approval before committing U.S. troops to combat.
Sen. Dick Durbin of Illinois, the No. 2 Senate Democrat, said that when Gadhafi started a violent crackdown on his people, Obama moved with "unprecedented speed," and when Gadhafi remained defiant, Obama worked with allies and the Arab nations. He called it a "prudent course of action for the president and for our nation."
But Republican Boehner, in a letter to the White House, said Obama still must provide a clear and robust assessment of the mission and how it will be achieved. Boehner did not call for a vote in the House on the commitment of U.S. military resources, as some lawmakers have demanded.
Deputy National Security Adviser Ben Rhodes told reporters traveling with the president that it would be "a matter of days" for the transition away from U.S. leadership.
An American Army general now oversees the campaign from Europe, and an American Navy admiral is the day-to-day commander from a floating command post off the Libyan coast.
"There is an agreement that NATO is going to play a very important role on command and control," Rhodes said, adding that details on the structure and shaping of the transition were still under discussion.
French and British officials said U.S., European, and Arab and African officials have been invited to London next week for political talks about Libya and how the NATO alliance will assume responsibility for a no-fly zone that has been established to keep Gadhafi's planes out of the air over his country.
Administration officials conceded there is no clear end to the fighting, although the Pentagon contended that Gadhafi's air force is essentially defeated and coalition planes are targeting more of his ground forces. U.S. officials said other countries are flying a larger share of the combat strikes alongside U.S. warplanes.
The Pentagon said that over the past day, the coalition flew 175 air missions, including noncombat flights. Of that total, 113 flights, or about 65 percent, were flown by U.S. planes, and 62 by other nations' aircraft. Three days earlier, the U.S. share was 87 percent, the Pentagon said.
Obama was asked in an interview with the Spanish-language network Univision if a land invasion would be out of the question in the event air strikes failed to dislodge Gadhafi. Obama called it "absolutely" out of the question.
Asked what the exit strategy is, Obama didn't lay out a vision for ending the international action, but rather said: "The exit strategy will be executed this week in the sense that we will be pulling back from our much more active efforts to shape the environment."
"We'll still be in a support role, we'll still be providing jamming and intelligence and other assets that are unique to us, but this is an international effort that's designed to accomplish the goals that were set out in the Security Council resolution," Obama said.
Gates said the allied mission in Libya was clear but the outcome was not.
"I think there are any number of possible outcomes here, and no one is in a position to predict them," Gates said. One possibility, he said, is that Gadhafi, who has ruled the North African nation for 42 years, could see more major defections from within his ruling circle or more divisions within his family.
Clinton sounded a similar note.
"Gadhafi has a decision to make," she told reporters at the State Department. "And the people around him each have decisions to make. The quickest way for him to end this is to actually serve the Libyan people by leaving."
Gadhafi has remained defiant, however, vowing to resist to the end. Clinton had said on Tuesday that the U.S. had received reports – of possibly dubious veracity – that some in Gadhafi's inner circle were looking for a way out.
In a telephone interview with reporters at the Pentagon from aboard his command ship, the USS Mount Whitney, in the Mediterranean, Navy Rear Adm. Gerard Hueber asserted that Gadhafi's air force had essentially been defeated. He said no Libyan aircraft had attempted to fly over the previous 24 hours.
"Those aircraft have either been destroyed or rendered inoperable," Hueber said.
He said, "There is widespread reporting indicating Libyan ground forces are engaged in fighting in a number of cities, including Ajdabiya and Misrata, and they are threatening a number of others, putting innocent civilians in grave danger."
Lolita Baldor reported from Cairo. Associated Press writers Donna Cassata, Anne Gearan, Pauline Jelinek and Matthew Lee contributed from Washington.