Libya's outgoing parliament, the General National Congress (GNC), has appointed a new prime minister in a move set to deepen the country's political split as warring factions vie for control of the country.

The GNC reconvened unilaterally on Monday in Tripoli and elected Islamist-backed Omar al-Hassi as prime minister, a parliamentary spokesman told the Reuters news agency.

The GNC said it replaced the House of Representatives (HoR), and tasked al-Hassi, a lecturer in political science at the University of Benghazi, with forming a "salvation government".

Local TV station, Alharar, said 94 politicians attended, meeting the minimum requirement for quorum.

The move is widely expected to fragment the country further, leaving it with two rival parliaments and governments.

Elected in June, the HoR replaced the GNC, ending the political dominance that factions linked to the Muslim Brotherhood had in the legislature.

The outgoing Islamist-dominated parliament refused to recognise the new parliament, which is dominated by liberals and federalists.

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The Islamists called for the GNC to reconvene after they accused parliament of complicity in air raids on allied militias battling to capture Tripoli international airport from the nationalist Zintan militia.

The political rivalry has been coupled with militia infighting, which has swept across the North African nation, and threatened to spill over into neighbouring countries.

On Monday, Libya's neighbours agreed not to intervene in the country's affairs, instead calling for a national dialogue.

"This joint initiative of the neighbouring countries is based on the main principles of... non-intervention in Libya's domestic affairs," a statement after a foreign ministers' meeting in Egypt read.

Libya's ambassador to Cairo had earlier demanded the international community to help protect oilfields, airports and other state assets.

Following a weeks-long battle over control of the capital's airport, Islamist militias claimed control of the facility, and urged the outgoing parliament to convene to "protect state sovereignty."

Political polarisation

Libya has grown increasingly polarised as clashes rage between rival armed groups and the country's fledgling parliament struggles to garner legitimacy.

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On one side, the Zintan brigades, based in the city some 130km southwest of Tripoli, are allied with anti-Islamist Qaaqaa and al-Sawaiq fighters, including some forces of toppled leader Muammar Gaddafi, and political allies who say they are a bulwark against Islamists taking over Libya.

Against them are fighters loyal to the western port of Misrata who are allied with the Islamist Justice and Construction party, an arm of the Muslim Brotherhood, who say they are fighting to purge ex-Gaddafi elements.

The Misrata forces have rejected the HoR, where liberals have campaigned for a federalist system.

Most of Tripoli has been calm, with fighting mainly restricted to the de facto frontlines in the south and parts of the west of the city. Fuel prices have soared on the black market as fighting has caused shortages.

Complicating Libya's security, in Benghazi an alliance of Islamist fighters and ex-rebels have joined together to battle Libyan armed forces, seizing a special forces military base last week and pushing the army outside of the city.

Source: Agencies