The government Thursday urged militias to withdraw from Tripoli after parliament sought help from ex-rebels, amid fears of clashes with forces backing a rogue general intent on ridding Libya of jihadists.
The call came as Khalifa Haftar, the ex-general, garners growing support among elements of the military and political class frustrated by Libya's continued instability three years after the overthrow of dictator Moamer Kadhafi.
Ahead of elections set for June 25, the cabinet of Prime Minister Abdullah al-Thani "issued an appeal to the chiefs of all armed brigades in Greater Tripoli" to leave the city and steer clear of politics, said government spokesman and Culture Minister Habib Lamine.
On Sunday, fighters from the powerful Zintan brigades, which demand the dissolution of the Islamist-dominated General National Congress and back Haftar, attacked the GNC's premises in Tripoli and set part of it on fire.
In response, GNC speaker Nuri Abou Sahmein called for help from equally powerful ex-rebels from the city of Misrata previously known for backing parliament to "protect the capital and the institutions of state".
But the Misrata brigades and its city council issued a statement this week saying they would keep their distance from both sides in a long-running political crisis pitting Islamists against liberals.
Even so, militia elements from Misrata entered a southern district of the capital Thursday, giving rise to fears of possible clashes with the Zintanis, and explosions were heard in the area.
The government statement said Abu Sahmein's decision to call in Misrata fighters "threatens the security of the city and its inhabitants".
Ironically, Thani resigned last month, but the man named to replace him, Ahmed Miitig, has not yet obtained a vote of confidence.
On Wednesday night, Haftar warned that Libya has become a "terrorist hub" and called for the formation of an emergency cabinet and legislative elections to be held.
His forces launched an assault last Friday on jihadists in the eastern city of Benghazi in which at least 79 people were killed.
That prompted the government to brand him an outlaw and claim he was attempting a coup, but Haftar insists he has no interest in power, just an end to the GNC.
- Haftar wants GNC out -
Once one of Kadhafi's top generals, Haftar returned to support the rebellion in 2011 and has emerged this year as the most serious challenge to the interim authorities.
Claiming to speak in the name of the army, he urged Libya's highest judicial authority "to form a civilian presidential high council tasked with forming an emergency cabinet and organising legislative elections."
Without explaining how this would come about, he said the presidential council he envisions would hand over power to an elected parliament.
This was the army's decision after the GNC, which some accuse of complicity with Islamist groups, had refused to step down "as demanded by the people", according to Haftar.
Successive governments have complained that the GNC's claim to executive power as well as legislative authority has tied their hands in achieving security.
The bottom line for many is that it has failed to restore security in a country where militias representing tribal, regional and ideological interests wield power to the detriment of the central government.
Libya has called an election for June to replace the GNC and try to resolve the power struggle, but violence among militias threatens to scupper the vote.
The GNC confirmed Thursday that the vote would be held on June 25, but with Haftar's latest demand its prospects are uncertain.
Haftar is backed by an elite army special forces unit in Benghazi, where Islamists are entrenched, by police brigades, officers at Tobruk air base, the powerful Al-Baraassa tribe from the east, the chief of staff of Libya's air defence units and the ex-rebel brigades from Zintan.
On the political front, Lamine became the first member of the government to back him, saying the GNC, "which protects terrorists, no longer represents me."
And Libya's UN ambassador, Ibrahim Dabbachi, has also declared his support.