AJDABIYA, Libya (AP) -- Moammar Gadhafi's ground forces recaptured a strategic oil town Wednesday as they made new inroads in beating back a rebel advance toward the capital Tripoli. Western powers kept up the pressure to force Gadhafi out with new airstrikes to weaken his military, hints that they may arm the opposition and intense negotiations behind the scenes to persuade Libya's leader of nearly 42 years to step down.

Airstrikes have neutralized Gadhafi's air force and pounded his army, but those ground forces remain far better armed, trained and organized than the opposition. Rebels have few weapons more powerful than rocket-propelled grenades and machine guns, and are no match for Gadhafi's tanks and longer-range heavy weapons.

That disparity was obvious as government forces pushed back rebels who had been closing in on the strategic city of Sirte, Gadhafi's hometown and a bastion of support for the longtime leader. Under heavy shelling, rebels retreated from Bin Jawwad on Tuesday and from the oil port of Ras Lanouf on Wednesday. Gadhafi's forces were shelling another oil port to the east, Brega, and some rebels were retreating farther still.

It looked like a mad scramble: Pickup trucks, with mattresses and boxes tied on, driving east at 100 mph (160 kilometers per hour).

Many regrouped east of Brega at the green, arching western gate of Ajdabiya, sharing water, dates and tuna sandwiches on a sandy, windswept plain next to two burned-out tanks and two burned-out cars from the airstrikes last week that drove Gadhafi's forces back.

"There's something strange about the way he attacked us today," said Abdullah Abdel-Jalil, a 31-year-old ambulance driver. "The Grad rockets, the tanks, the quantity of it all, he's stronger than we thought. It's way too intense."

NATO planes flew over the zone where the heaviest fighting was under way and an Associated Press reporter at the scene heard explosions, in contrast with Tuesday, when rebel fighters' pleas for airstrikes went unheeded. U.S. Marine Corps Capt. Clint Gebke, a spokesman for the NATO operation aboard the USS Mount Whitney, said he could not confirm any specific strikes but Western aircraft were engaging pro-Gadhafi forces.

Whatever air support NATO provided, however, did not appear to turn the situation at all to the rebels' advantage.

"We don't know why they're not here," said Moftah Mohammed, a 36-year-old rebel soldier. "Our forces are mainly on the side of the main road. We've heard Gadhafi's forces are pushing deep into the desert" in an attempt to head off rebel forces. "We don't want to be stuck in the middle of that."

Mohammed, however, thought loyalist forces would stop pursuing the rebels. "Gadhafi aims to take back Ras Lanouf and Brega because he's running out of oil. I think he'll stop there," he said.

As Gadhafi's forces push rebels toward their de-facto capital Benghazi, some 140 miles (220 kilometers) northeast of Brega, pressure is growing for NATO members and other supporters of the air campaign to do more.

Prime Minister David Cameron said Britain believes a legal loophole could allow nations to supply weapons to Libya's rebels - but stressed the U.K. has not decided whether it will offer assistance to the rebels.

U.S. Secretary of State Hillary Rodham Clinton said Tuesday that Washington also believes it would be legal to give the rebels weapons. As to whether the country would do so, President Barack Obama told NBC, "I'm not ruling it out, but I'm also not ruling it in."

France, one of the strongest backers of international intervention in Libya, believes arming rebels would require a new U.N. resolution; the existing one includes an arms embargo. But Foreign Minister Alain Juppe said, "We are ready to discuss it with our partners."

Under the U.N. resolution authorizing necessary measures to protect civilians, nations supplying weapons would need to be satisfied they would be used only to defend civilians - not to take the offensive to Gadhafi's forces.

Cameron's spokesman Steve Field said British and other diplomats were involved in negotiations with the rebel leadership in Benghazi partly to gauge if the opposition would be trustworthy allies.

"We are in the process of talking to those people and learning more about their intentions," Field told reporters.

Another possibility is to ramp up airstrikes, which so far have been conducted with the stated goal of helping civilians, rather than with helping the rebels advance. But even the airstrikes conducted so far have been criticized by world powers such as Germany and Russia.

There are also hopes for a diplomatic solution.

Italian Foreign Minister Franco Frattini said negotiations on securing Gadhafi's exit were being conducted with "absolute discretion" and that there were options on the table that hadn't yet been formalized.

"What is indispensable is that there be countries that are willing to welcome Gadhafi and his family, obviously to end this situation which otherwise could go on for some time," he said.

But the Italian diplomat insisted immunity for Gadhafi was not an option. "We cannot promise him a 'safe-conduct' pass," he stressed.

Libyan Foreign Minister Moussa Koussa visited Tunisia briefly, but there was no word if this was linked to the secret talks.

Uganda appeared to be the first country to publicly offer Gadhafi refuge. The spokesman for Uganda's president, Tamale Mirundi, told the AP on Wednesday that he would be welcome there.

France - which was the first nation to formally recognize the Libyan rebels - confirmed that a diplomatic presence was established in Benghazi on Tuesday. Foreign Minister Alain Juppe stressed that Antoine Sivan will not be a formal ambassador but rather a diplomat there to establish relations with the Council in Benghazi.

Mahmoud Shammam, a spokesman for the Libyan opposition, told reporters in London that, properly equipped, rebels "would finish Gadhafi in a few days."

"We do not have arms. We ask for the political support more than we are asking for the arms, but if we get both that would be great," Shammam said.

Britain, meanwhile, said it expelled five Libyan diplomats loyal to Gadhafi, including the country's military attache, because of their intimidation of opposition supporters and their potential threat to the U.K.'s national security.