UN envoy Bernardino Leon, who held talks for the first time with retired General Khalifa Haftar, said "time was running out" to tackle the country's political and security crises.
"Libyans need to unite and work towards solving their differences if they want to save their country," Leon was quoted as saying in a statement issued today, a day after his meetings.
Leon also met with representatives of Libya's internationally recognised government in Tobruk and with rival officials in Tripoli, the statement added.
Haftar, a controversial figure, launched a May offencive against mainly Islamist fighters in control of the second city of Benghazi.
He was initially accused by Libya's internationally recognised government of carrying out a coup but relations have since thawed as Haftar's fighters and state forces jointly battle militias.
Libya's parliament, which took refuge in the remote east after fighters from the predominantly Islamist Fajr Libya militia stormed the capital in August, has asked Haftar and other retired officials to be officially reinstated into the army.
Also today, a rocket attack targeted the Tripoli headquarters of a private television station close to Islamist factions, causing damage but no casualties.
Al-Nidaa television said its offices had been hit by two rocket-propelled grenades but vowed that the attack would not force the channel off air.
