TRIPOLI A U.N. delegation held talks in Tripoli on Friday to try to broker a ceasefire between armed factions that have turned the Libyan capital and Benghazi into battlegrounds.
The violence has sharpened Libya's political divisions, and on Friday several thousand people marched in Tripoli, Benghazi and Misrata, to protest against the newly elected parliament that Western countries hope will facilitate reconciliation.
The U.N. delegation, led by a representative of the United Nations mission in Libya, UNSMIL, aims to end the violence, help displaced Libyans and alleviate shortages of food and basic services, it said in a statement.
"UNSMIL is working closely with the international community in a joint effort to achieve a durable and sustainable ceasefire," it said, giving no details on whom U.N. officials were meeting in Tripoli.
The United Nations and most Western countries have pulled all of their diplomats stationed in Libya to escape the worst fighting since Muammar Gaddafi's fall three years ago.
There was sporadic shelling on Friday in the capital, one of the quietest days since the clashes erupted between Islamist-allied Misrata brigades and fighters from the western town of Zintan who control the international airport.
Benghazi was also quieter a week after an alliance of Islamist fighters and former rebels took a special forces army base and a police headquarters.
Since the fall of Gaddafi, Libya's fragile government is unable to impose authority on groups of former rebels who refuse to disband and are allied with competing political factions battling for post-war dominance.
Even if a ceasefire is reached, a broader political agreement between the two factions may prove elusive.
Political fighting between Libya's Islamist forces and a more nationalist-leaning alliance paralyzed the last parliament, in which the Islamist Justice and Construction Party, seen as close to the Muslim Brotherhood, was more influential.
The newly elected House of Representatives which replaced the General National Congress, has been holding sessions in the eastern city of Tobruk, far from the clashes in Libya's two main cities, and has called for a unity government.
Islamist factions have rejected the sessions held in Tobruk as unconstitutional.
Several thousand people rallied in Tripoli, Benghazi and Misrata against the Congress, and Tripoli's police fired into the air to disperse the crowd when other, pro-parliament protesters, charged their rivals.
Armored police trucks closed off streets in central Tripoli when rival protesters opened fire or tossed bricks at each other.
Fighting since last month over Tripoli airport involves two loose factions of ex-rebels.
On one side are Zintanis, including some former Gaddafi forces, who present themselves as a bastion against Islamist fundamentalists and the Muslim Brotherhood.
Against them are brigades from the western port of Misrata, allied with Islamist political forces and other militias, who say they are fighting to clear out remnants of Gaddafi's army.
Zintan forces, who control the airport, have said they are ready for a ceasefire, but Misrata forces say they will not accept any agreement until the Zintan forces leave Tripoli.
Acting Prime Minister Abdullah al-Thinni said Libya was at a "crossroads", and called on Western countries to help the country build its army and state institutions.
"To be honest, Western countries do not want any military intervention because of what happened in the other countries such as Syria and Iraq," he told Al-Hurra television in an interview conducted in Washington where he was meeting U.S. officials.
"But we asked for more involvement in the Libyan issue, as the international community already moved to help the Libyan revolution. So they should complete the process of building the Libyan state and its institutions."
(Editing by Robin Pomeroy)