Fighter jets have targeted forces under the command of Libya's renegade General Khalifa Haftar in a bid to halt his military assault on the capital, Tripoli, that threatens to further destabilise the country.

As clashes continued on the outskirts of the city on Saturday, human rights groups warned of civilians suffering possible abuses if the fighting escalated, joining a chorus of international powers calling for a cessation of all hostilities.

Haftar's self-proclaimed Libyan National Army (LNA) said in a statement on Saturday it was carrying out an operation to secure Tripoli's former international airport, which sits some 30km south of the city, and would later use it as a launching point for missions aimed at seizing key sites within the capital.

Al Jazeera's Mahmoud Abdelwahed, reporting from Tripoli later on Saturday, said that high-ranking GNA officers "confirmed they are in full control" of the airport.

"In fact, as they say, they are pushing back Haftar's forces from the outskirts of Tripoli towards the city of Gharyan," he added, referring to a city south of the capital that was taken by the LNA on Thursday.

The wrestle over the airport comes two days after Haftar ordered the eastern forces to march on Tripoli, which is controlled by the United Nations-backed Government of National Accord (GNA) and protected by an array of militias. The LNA is allied to a parallel administration based in the east of the oil-rich North African country.

'Sporadic fighting'

Al Jazeera's Abdelwahed said the area surrounding the airport and a clutch of other nearby neighbourhoods were "witnessing military deployments and sporadic fighting", accounting for one of four "major confrontation" zones.

"These areas are on the southern outskirts of Tripoli, near the western gate of Tripoli … and two major front lines in the west of Libya," Abdelwahed said, adding clashes could erupt in each of the locations "at any time".

The LNA's advance has escalated a power struggle that has splintered Libya into a patchwork of the competing power bases since the overthrow of former leader Muammar Gaddafi in 2011.

In response to Haftar's drive, the GNA has authorised air attacks against "any military activities by [LNA] forces trying to enter the capital", Abdelwahed said.

Pro-GNA forces have also amassed in the city in a bid to push back the LNA offensive, with military units and detachments arriving from cities such as Misrata and Zawiya, Abdelwahed added.

"We are getting reports from the eastern outskirts of Tripoli saying that more military units and detachments from Misrata are joining the battle, moving towards the southern outskirts of Tripoli," he said.

As fresh fighting between the competing factions flared, LNA forces alleged they had been targeted by four air raids, including one in the al-Aziziya region, which sits about 50km south of the capital.

"Any jet fighter flying over Tripoli will not be allowed and will be targeted, the air base it came from will also be targeted," Haftar's spokesman, Ahmed al-Mesmari, said. He added that no LNA troops were injured in the raids.

UN pushes for reconciliation conference

Amid the escalating tension, an array of international leaders and organisations have called for all parties to put an end to the ongoing conflict and instead focus their efforts on planning elections to resolve Libya's prolonged instability.

On Friday, UN Secretary-General Antonio Guterres said he was "deeply concerned" over the possibility of "bloody confrontation in and around Tripoli".

"The UN is committed to facilitating a political solution and, whatever happens, the UN is committed to supporting the Libyan people," Guterres said. (Aljazeera)

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