Libya: French war planes begin allied strikes to halt Gaddafi offensive (UPDATES) (VIDEO)

BENGHAZI, Libya — French war planes entered Libyan air space Saturday in an attempt by allied Western forces to push back an assault by fighters loyal to Libyan leader Muammar Gaddafi. Meanwhile, a battle raged for Benghazi, the country's last-remaining rebel stronghold.

French president Nicolas Sarkozy said Saturday that an operation supported by France, Britain and the U.S., and backed by Arab nations, was halting air attacks by Gaddafi's forces and would continue unless the Libyan leader ceased fire.

Reuters quoted a French military source as saying that France had five war planes operating over Libya, including an AWACS reconnaissance plane and four attack aircraft, two Rafales and two Mirages. They fired on a Libyan military vehicle, CNN reported.

Military action could be halted at any time if Gaddafi stopped his forces attacking, Sarkozy reportedly said.

The action was in response to attacks Saturday morning by Gaddafi's forces on Benghazi despite his promises of a cease-fire.

Residents of the city, Libya's second-largest, awoke Saturday to the sound of jets flying low overhead, a show of force from Gaddafi that was in open defiance of the no-fly zone authorized by the United Nations on Thursday.

Leaders from the United States, Britain, France and Arab countries planned to meet Saturday in Paris to discuss the new U.N. resolution and how military action will be executed. French President Nicolas Sarkozy, meanwhile, said French military flights over Libya had already begun to strike back.

The U.N. resolution enables allies to "take all necessary measures" to protect civilians.

Earlier Saturday, Gaddafi issued defiant messages to international powers, CNN reported.

"I have all the Libyan people with me and I'm prepared to die. And they are prepared to die for me. Men, women and even children," Gaddafi said in a letter addressed to President Barack Obama and read to reporters by a government spokesman in Tripoli on Saturday.

Rebel fighters, in a rare victory earlier in the day, managed to shoot down one of Gaddafi's planes mid-flight. The plane crashed in the western side of the city in a ball of fire and smoke.

The Gaddafi forces used Girad Soviet-made rockets to pound the outskirts of the city, destroying homes and incinerating rebel cars. Loyalist tanks apparently made it to the west of Benghazi before being captured. The streets showed signs of tank tracks, and cars had been flattened as if run over by tanks. Rebel soldiers claim to have captured eight of Gaddafi’s tanks.

Gaddafi’s forces attempted to enter Benghazi from several sides, prompting rebel forces to push back with a wave of trucks.

During a battle for the western gate, where rebel fighters gathered with small arms and rocket-propelled grenades, toyotas mounted with anti-aircraft guns pushed forward. Bullets flew from different directions sporadically.

Grenades and bullets left homes on the western side of Benghazi pockmarked. Residents said Gaddafi fighers wearing civilian clothes were holed up in several building from which they had begun randomly shooting cars on Saturday morning.

Locals showed GlobalPost at least three civilian cars hit by bullets, one with blood stains on the passenger and driver’s sides.

Just a few miles outside Benghazi laid the burned remains of what looked like three rebel soldiers inside a truck carrying a heavy weapon. Rebels looted a nearby army barracks that Gaddafi forces had occupied overnight and where they had left fresh grenade rounds in boxes.

On the outskirts of the front line and under fresh attacks from Gaddafi's Girad rockets, some rebels fled the onslaught Saturday and others pressed on.

The battle for Benghazi shifted continuously throughout the day Saturday.

Rebels pushed Gaddafi forces back Saturday morning but then retreated from returning rocket fire, giving Gaddafi forces a chance to re-enter the city.

“Where is Obama?” one man asked. “Yesterday Gaddafi says he’s not attacking Benghazi. Today there’s tanks and artillery.”

Gaddafi's forces entered Benghazi while the rebels were erecting a concrete barrier to defend their headquarters from attacks, a rebel spokesman told Reuters.

Pro-government forces also bombed the road to the airport.

The Libyan government denied its forces were fighting in or around Benghazi and blamed rebels for breaking the cease-fire.

Fresh fighting was also reported in the cities of Misurata and Ajdabiya, Al Jazeera reported.

President Barack Obama has ordered Gaddafi to stop all attacks on Libyan civilians or face military action from the United States and its allies.

Obama — in his strongest comments yet from the White House on events in Libya — said Friday that Gaddafi had to pull forces back from major cities or he would be forced to.

“If Gaddafi does not comply with the resolution, the international community will impose consequences, and the resolution will be enforced through military action,” Obama said.

In line with the U.N. resolution, Obama ruled out sending American ground forces into Libya and said the United States would take a supporting role with European and Arab allies in the lead, AP reports.

Speaking Friday, the president gave a list of reasons for why military action might be necessary.

"Left unchecked, we have every reason to believe that Gaddafi would commit atrocities against his people," he said, as reported in the AP. "Many thousands could die. A humanitarian crisis would ensue. The entire region could be destabilized, endangering many of our allies and partners. The calls of the Libyan people for help would go unanswered. The democratic values that we stand for would be overrun."

Obama's forceful language and threats of military action come after weeks of hesitation and uncertainty concerning how the United States should respond to the crisis.

— Hanna Ingber Win contributed to this report from Mumbai