At least 174 people have been killed and more than 18,000 displaced since Haftar ordered his forces to march on Tripoli on April 4, according to UN figures
United Nations Security Council diplomats began negotiations Tuesday on a British-drafted resolution that would demand an immediate ceasefire in Libya after forces loyal to commander Khalifa Haftar launched an offensive on Tripoli.
The proposed text seen by AFP warns that the offensive by Haftar's Libyan National Army (LNA) "threatens the stability of Libya and prospects for a United Nations-facilitated political dialogue and a comprehensive political solution to the crisis."
The council "demands that all parties in Libya immediately de-escalate the situation, commit to a ceasefire, and engage with the United Nations to ensure a full and comprehensive cessation of hostilities throughout Libya," the draft says.
After Britain circulated the text late Monday, a first round of negotiations was held during which Russia raised objections to references criticizing Haftar, diplomats said.
"They were very clear. No reference anywhere," a council diplomat said.
Britain was hoping to bring the measure to a vote at the council before Friday, but diplomats pointed to Russia's objections as a hurdle.
At least 174 people have been killed and more than 18,000 displaced since Haftar ordered his forces to march on Tripoli on April 4, according to UN figures. A rocket attack on the city killed two people and injured four on Tuesday.
Last week, Russia blocked a draft council statement that would have called on Haftar's forces to halt their advance on Tripoli.
Influence in Libya
The proposed measure echoed a call for a ceasefire by UN Secretary-General Antonio Guterres, who was in Libya to personally advance prospects for a political solution when the offensive was launched.
Haftar, seen by his allies Egypt and the United Arab Emirates as a bulwark against Islamists, has declared he wants to seize the capital, now controlled by a UN-recognized government and an array of militias.
Haftar backs a rival administration based in eastern Libya that is refusing to recognize the authority of the Tripoli government.
The draft resolution calls on all sides in Libya "immediately to re-commit" to UN peace efforts and urges all member-states "to use their influence over the parties" to see that the resolution is respected.
Resolutions adopted by the council are legally binding.
Diplomats have long complained that foreign powers backing rival sides in Libya threatened to turn the conflict into a proxy war.
Saudi Arabia is also seen as a key Haftar supporter, while Qatar - which has tense ties with Riyadh and Abu Dhabi - has called for stronger enforcement of the UN arms embargo to keep weapons out of Haftar's hands.
Russia and France, two permanent council members, have praised Haftar's battlefield successes in defeating Libyan armed groups aligned with the Islamic State in the south of the country.
Haftar's offensive on the capital forced the United Nations to postpone a national conference that was to draw up a roadmap to elections, meant to turn the page on years of chaos since the 2011 ouster of Moamer Kadhafi.
Guterres has said that serious negotiations on Libya's future cannot resume without a ceasefire.