The UN says the two sides have agreed on a plan for implementing a ceasefire deal reached last month.
Libyans at the United Nations-led talks in Tunisia have started to hammer out the powers of a proposed transitional government amid cautious hopes for an end to a decades-old conflict.
But tensions simmer as the rival administrations vying for control of the oil-rich North African country also held separate military talks in the central Libyan city of Sirte.
The Tripoli-based unity government warned a landmark ceasefire agreed last month could be in peril, saying their Moscow-backed rivals had launched live-fire exercises and accusing Russian mercenaries of blocking their delegation from landing at an airport near Sirte.
“We do not want these moves to cause the failure of peaceful dialogue,” the military command of the Tripoli-based Government of National Accord (GNA) said in a tweet on Thursday.
“But we will not accept to negotiate under the duress of mercenaries and their air defences.”
A major oil producer, Libya has been witnessing violence since a NATO-backed uprising in 2011 overthrew and killed veteran leader Muammar Gaddafi.
The country has since 2015 been dominated by armed groups and divided between two bitterly opposed administrations: the UN-brokered GNA and a rival administration in the east, backed by renegade military commander Khalifa Haftar.
Haftar, who is backed by Egypt, Russia and the United Arab Emirates, launched an offensive on Tripoli in April 2019 but was beaten back in June by the GNA with military support from Turkey in an operation that pushed his troops back to the central coastal city of Sirte, Gaddafi’s birthplace.
The fighting left hundreds dead and displaced tens of thousands of people.
The warring factions returned to the negotiating table in September in UN-supported talks held in Morocco, Egypt and Switzerland.
The UN Libya mission, UNSMIL, is also leading the military talks near the ceasefire line in Sirte.
Interim UN Libya envoy Stephanie Williams said the latest round of talks was “the best opportunity to end the division” since Haftar’s failed offensive.
Delegates in Tunisia had agreed to a preliminary road map for “free, fair, inclusive and credible presidential and parliamentary elections” within 18 months, she said late on Wednesday.
But observers have questioned the legitimacy of the 75 delegates, selected by the UN to represent existing institutions and the diversity of the Libyan society.
Also, the latest negotiations, which follow multiple failed peace talks, remain prey to potential spoilers including armed groups and foreign powers.
In a stark reminder of the lawlessness that continues to plague Libya, prominent lawyer and rights activist Hanan al-Barassi was shot dead in the street in the eastern city of Benghazi on Tuesday by unidentified gunmen.
The timing of her killing prompted speculation as to whether it was meant to spoil the UN-led talks.
Foreign players also continue to loom large in the developments. The GNA this week accused the Wagner Group, a Russian paramilitary organisation backing Haftar, of preventing its delegation at the Sirte talks from landing at the nearby Qardabiya airbase.
The shadowy Russian military contractor, reputed to be close to the Kremlin, has been accused of numerous violations in Libya.
The GNA’s military command, in a series of angry tweets, warned of threats to “the prospects of a permanent ceasefire”.
“Why does our delegation have to land 170 kilometres [105 miles] further east despite the fact there are two airports in Sirte?” spokesman Mohammed Gnunu wrote.
The GNA military command also cited live fire exercises by pro-Haftar forces in the area and said people from Haftar’s “inner circle” were managing the meetings.
But UNSMIL said the joint commission had met on Thursday in a “positive spirit”.
The two sides “agreed on the withdrawal of all foreign forces and mercenaries from their positions on the front lines, to be transported to Benghazi and Tripoli as a first step, to start the process of their departure from Libyan territory,” said Salim Raad, head of UNSMIL’s security institutions section, adding that the two sides had agreed to meet again.
The vast Qardabiya airbase is in a key location for long range air defences, sitting roughly in the middle of the Mediterranean’s southern coast.
Jack Watling, a research fellow at the Royal United Services Institute think-tank in London, said Russia was seeking to maintain leverage in the talks.
“Local air defenders feel safer with a sanitised airspace,” he said. “But Russia is also showing that it can sabotage the [military] talks to maintain leverage.”
Moscow could use its presence to demand the lifting of sanctions imposed over its 2014 annexation of Crimea, he said.
“Has [the Qardabiya incident] sabotaged the talks? Probably not, but Russia has highlighted that it could if it wanted to,” he said.