As part of their mission in Libya, the United States and its European allies have unleashed a high-tech assault from the air, deploying AWACS spy planes, unmanned aircraft and sophisticated satellite systems.

But in the rebels’ operational command center in eastern Libya, there are no television screens beaming satellite images, no detailed maps with Global Positioning System coordinates. They don’t even have a direct phone line to their NATO counterparts.

So when a rebel officer on the front line called in one recent morning in need of help, Brig. Gen. Abdulsalam al-Hasi had little choice. He walked down the corridor and asked the American and European advisers in his command center to request a NATO airstrike — and then prayed for quick action.

“Sometimes they are late, very late,” said Hasi, shaking his head.

The episode highlights an inescapable dilemma facing the rebel military. After more than three months of stalemate, the rebels’ quest to remove Gaddafi from power depends almost entirely on a NATO force that they do not control and that insists its mandate is restricted to protecting civilians. Rebel commanders can only ask NATO for help, then wait and hope.

A few weeks ago, there was virtually no coordination between the rebels and NATO. The situation has since improved, rebel commanders acknowledge.

But top rebel military officials say the still low level of coordination and lack of resources means they are being left out of key decision-making in a war they launched.

“We’re talking to them through their switchboard,” Hasi said. “There’s no direct line. It’s like ordering room service.”

The rebel officers complain that NATO has not posted a liaison officer in the command center. Hasi and his team do not speak to the AWACS controllers to coordinate airstrikes, and they get little feedback from their NATO counterparts.

“We have no contact with anyone except those people that are next door,” Hasi said. “We need more contact with NATO. We need more of everything.”

But even as he complained, Hasi was wary of criticizing NATO too much. He knew the rebels’ hopes of overthrowing Gaddafi, who has been in power for 41 years, hinged on attacks by the alliance’s forces.

“Mostly, they are doing good. They are improving,” he said.

Confines of a mandate

NATO officials say their decision to keep the rebels at arm’s length was deliberate.

“For us, it’s all about not wanting to contravene or jeopardize the U.N. mandate that we’re following,” said a NATO official in the alliance’s headquarters in Brussels, speaking under NATO ground rules that he not be named. The U.N. resolution authorizing military action in Libya speaks only of protecting civilians from attacks by Gaddafi’s forces, he said.

“We cannot be [the rebels’] air power,” the official said. “This was a popular public uprising, and it has to unfold that way, in a natural way. It’s not for us to do any more in terms of support.”

The grumblings from top Libyan rebel military officials come as NATO intensifies its air campaign against Gaddafi’s forces to break the stalemate. Battle lines are shifting rapidly and expanding to areas in the mountainous western region. France and Britain have sent attack helicopters to launch more precise strikes against Libyan government forces.

NATO announced Wednesday that it was extending its mission in Libya by 90 days, a largely symbolic move that nevertheless suggested no imminent letup in the military pressure on Gaddafi’s forces. But with no troops on the ground, NATO might increasingly need to rely on the rebels to coordinate pinpoint attacks.

‘We have nothing’

The command center is inside a brown, one-story building on a large government-owned campus. Rebel officials requested that the exact location not be revealed for security reasons. On one end of the corridor is Hasi’s spacious office; on the other end is a room in which the Western advisers work. Hasi’s team of analysts works in between.

Rebel commanders declined a request to interview the Western advisers, whom they refused to identify. Hasi said the advisers include Americans, British, French, Spaniards and Qataris, most of whom appear to have a direct line to NATO officials in Brussels. Officers from the CIA and special operations troops from Britain, France and other allies are also thought to be working on the ground with the rebels.

Hasi’s analysts field phone calls from all over Libya, collecting information on movements by Gaddafi’s forces, accounts of deaths, and pleas for fuel and other assistance. They try to ensure that the reports are accurate, and, if there’s an emergency, such as the threat of an imminent strike by government forces, they alert Hasi, who relays the information to the Western advisers.

Analyst Omran Senussi, 29, a former civil engineer, said he and his team are always concerned about the safety of civilians and rebel fighters. Since NATO strikes began in mid-March, there have been at least two “friendly fire” incidents, which killed more than a dozen rebel fighters.

“We have to move very carefully,” Senussi said.

An official at NATO’s operational headquarters in Naples said information from the rebels did filter up to the alliance’s command. “Various allies have people on the ground and are working with the Transitional [National] Council,” he said, referring to the body established by opposition leaders in their de facto capital, Benghazi.

“Those guys do pass information back up to us. . .  That may be a little less than some people would like,” he said, but NATO had thought it was important to draw clear lines.

But that could change. The official said NATO was discussing whether to send a liaison team to Benghazi.

For now, though, Hasi and other Libyan rebel commanders insist that NATO is not listening to them closely enough and that it is not sharing intelligence it gets from other sources.

“NATO receives information from everyone. We are the official operational command center of the Free Libyan Forces,” Hasi said.

Like other Libyan military officials, Hasi defected shortly after the populist rebellion erupted Feb. 17. Before the revolution, he was a top commander in eastern Libya, in charge of the nation’s special forces.

A short, sturdy man with gray hair, Hasi speaks English, often peppered with jokes. But he does not mince words when talking about the state of the rebels’ military. “We have nothing. We are starting from a big zero.”

Hasi said that the rebel fighters need more advanced reconnaissance technology and that they lack critical equipment, including long-range radios, armored vests and avionic infrared binoculars. He does not even have enough four-wheel-drive vehicles, he said.

But sometimes he gets what he wants. A little more than two hours after he walked down the hall, Hasi received a call from the field commander near the front line between the towns of Ajdabiya and Brega. Hasi quickly flashed a smile and nodded. NATO had come through with swift assistance.

As the commander had reported, “I can hear the planes.”

Correspondent Michael Birnbaum in Berlin contributed to this report.