Black smoke billows over the skyline as a fire at the oil depot for the airport rages out of control after being struck in the crossfire of warring militias battling for control of the airfield, in Tripoli, Libya. (AP Photo/Mohammed Ben Khalifa)

Cairo - The Libyan government warned Monday of a potential “human and environmental disaster” as two fuel tanks at an oil depot near Tripoli airport burned out of control amid fighting between rival militias.

In statements published on its website, the interim government called on residents living within three kilometres of the Brega Oil and Gas Company's depot to leave the area.

The government demanded that Islamist militias and their rivals halt their two-week-long struggle for control of the airport and surrounding area.

Libyan news site al-Wasat quoted National Oil Corporation spokesman Mohammed al-Hawari as saying that Greece and Italy had agreed to send firefighting planes to Libya on condition that fighting in the area ended.

Local firefighters had been unable to extinguish the blaze despite exhausting their supplies of water and had left the scene, al-Hawari said.

The fire began overnight when a rocket hit a container with 6.6 million litres of fuel, al-Wasat reported. Overall, the tankers in the warehouse contain 90 million litres of fuel. At least 97 people have been killed and more than 400 injured since the fight for the airport began, al-Wasat reported on Sunday quoting a Health Ministry official.

Islamist-leaning militias allied to the leadership of Libya's interim parliament launched an offensive on the facility on July 13, taking on forces from the western town of Zintan, who have controlled it since the overthrow of Muammar Gaddafi in 2011.

The fighting has cause heavy damage to airport buildings and aircraft, prompting the authorities to suspend flights. Fighting between Islamist militias and army units in Benghazi killed 38 people on Sunday. Meanwhile, Germany announced that it had withdrawn all diplomats from its embassy in Tripoli.

Along with other Western countries, it had already warned its citizens to leave. Thailand and Egypt also took steps to evacuate their nationals from the troubled North African state.

Thailand's junta leader Prayuth Chan-ocha told state media that some 1 500 Thai nationals would be evacuated to Tunisia where they will board a chartered plane back to Thailand, while Egypt sent a consular mission to Tunis to oversee the evacuation of its citizens.

On Saturday, the United States shut down its embassy in Libya and relocated all its staff to Tunisia. Fighting has since spread to the area around the embassy, al-Wasat reported.