SIRTE, Libya - Libyan revolutionary forces battled their way into the eastern outskirts of Moammar Gadhafi's hometown of Sirte on Tuesday, trying to link up with anti-Gadhafi fighters besieging the city from the west, commanders said.

More than a month after sweeping into Tripoli and ending Gadhafi's nearly 42-year rule, Libyan forces still face fierce resistance from the fugitive leader's supporters on three fronts -- in Sirte, the town of Bani Walid southeast of the capital and in pockets in the country's vast desert south.

Some of the heaviest fighting has taken place in Sirte, which anti-Gadhafi forces first attacked nearly two weeks ago. They have since pulled back in the face of fierce resistance from Gadhafi loyalists holed up inside.

Revolutionary forces have staked out positions to the west and south of the city, and commanders said anti-Gadhafi forces advancing on Sirte from the east also pushed into the city's outskirts Tuesday.

Abdel-Basit Haroun, a rebel field commander, said his fighters reached a roundabout less than six miles (10 kilometres) east of the city centre. He said the plan was for the forces from the east and west to meet inside Sirte.

"We are almost there, but the hard phase of the takeover has just begun," Haroun said. "We stopped using heavy weapons because the residential areas are packed with families, children and women. We are also facing snipers all over the rooftops of tall buildings."

Haroun said foggy weather was also not helping the battle.

He said his forces had installed checkpoints around Sirte to arrest any Gadhafi troops who try to slip out of the city alongside crowds of fleeing civilians.

A revolutionary brigade commander on the city's western front, Al-Tohami Abu Zayan, said anti-Gadhafi forces can take Sirte "whenever we choose," but are holding back to protect civilians. He said fighters are communicating with members of Gadhafi's tribe, the Gadhadfa, to find ways for them to leave the city.

"Now we have some communication by satellite phone with the Gadhadfa and other tribes to provide them with safe passages to safe areas," he said, adding that those who leave will have to surrender their weapons. The revolutionary forces will also detain any of those suspected of fighting for Gadhafi.

For nearly two weeks, revolutionary forces have regularly fired mortar rounds, Grad rockets and tanks shells into the city. Civilians have fled the city for days, driven out by the fighting as well as deteriorating living conditions, including shortages of food, water and medicine. Many said that loyalist forces inside prevent them from leaving, turning them back at checkpoints. Most who make it out said they had to take hidden dirt roads to escape.

The fighters besieging Sirte have received a boost in recent days from NATO, which has played a key role in pounding Gadhafi's military forces since first intervening in the Libyan civil war with an air campaign in March.

British Maj. Gen. Nick Pope said Royal Air Force Aircraft struck targets in Sirte and Bani Walid on Monday.

"In Sirte, a formation of Tornado GR4s attacked ammunition stores, destroying their targets with Paveway guided bombs," he said.

He said strikes also hit Bani Walid after NATO reconnaissance identified a psychological warfare centre and a firing position used by Gadhafi forces.

NATO also said on Tuesday that about 200,000 Libyan civilians are still threatened by forces loyal to the country's former regime, primarily in the cities of Sirte and Bani Walid.

"Remaining Gadhafi forces refuse to recognize their defeat," said NATO spokesman Col. Roland Lavoie. "As a last resort, they are hiding in civilian areas."

Lavoie told a news conference Tuesday in Naples, Italy, that drinking water, food, electricity, medicine and fuel were in short supply in those cities, putting the population under pressure.

Forces loyal to the former regime are looking for Gadhafi opponents, taking them hostage and sometimes executing them, Lavoie said. But he said the loyalists cannot hold out long and NATO's mission would soon end.

In Algeria, where Gadhafi's wife, daughter and two of his sons fled last month, a Foreign Ministry official said Algerian authorities have threatened the Gadhafis with expulsion if they make comments to the media.

The warning comes days after recorded comments by Gadhafi's daughter, Aisha, were broadcast on Syrian-based TV. An Algerian newspaper report also alleged some of the deposed Libyan leader's relatives had flown to Egypt.

The ministry official, speaking on condition of anonymity, insisted Tuesday that Gadhafi's relatives remain in Algeria. His wife, daughter Aisha and two sons fled to Algeria after Tripoli's fall late last month.

Aisha said in an audio recording aired Friday on Syrian-based Al-Rai TV that her father was in high spirits and fighting alongside his supporters. The Algerian foreign minister has called such public comments "unacceptable."