The Libyan National Army of commander Khalifa Haftar continued its push towards Tripoli on Friday by capturing several regions near the capital.
They have taken control of the areas of Qasr ben Ghashir, Wadi al-Rabie and Suq al-Khamis, said the LNA in a statement.
The developments on the ground coincided with a meeting between Haftar and UN Secretary-General Antonio Guterres in Benghazi.
“I leave Libya with a heavy heart and deeply concerned. I still hope it is possible to avoid a bloody confrontation in and around Tripoli,” Antonio Guterres said on Twitter.
“The UN is committed to facilitating a political solution and, whatever happens, the UN is committed to supporting the Libyan people.”
Al-Arabiya TV said Haftar told Guterres that the operation would continue until terrorism is defeated.
Guterres earlier went to Tobruk, another eastern city, to meet Aguila Saleh, president of the House of Representatives, which is also allied to Haftar.
Guterres had been in the capital this week to help organize a national reconciliation conference planned for later this month.
On Thursday, Saleh welcomed the LNA offensive. After the meeting with Guterres, his spokesman said they had discussed ways to end the crisis and the planned conference, without giving details.
Also on Thursday LNA forces took Gharyan, about 80 km (50 miles) south of Tripoli after skirmishes with forces allied to the Government of National Accord of Fayez al-Sarraj.
The conference the United Nations is helping to organize is aimed at forging agreement on a roadmap for elections to resolve the prolonged instability in Libya.
Germany called an emergency meeting of the UN Security Council due to the military escalation.
Kremlin spokesman Dmitry Peskov stated Moscow supported a negotiated political settlement to Libya’s problems that ruled out any new bloodshed.
“We are closely following the situation in Libya,” he told reporters. “Of course, we consider that the most important thing is that (military) operations there do not lead to bloodshed. The situation should be resolved peacefully.”
The General Secretariat of the Organization of Islamic Cooperation (OIC) expressed its concern about the military escalation in the Libya. It called on all parties to exercise maximum restraint and avoid any armed escalation that could lead to chaos.
Dialogue is the only way to resolve disputes, it added, stressing its support for UN efforts to achieve comprehensive national reconciliation.
Tunisia has tightened control on its border with Libya in response to the renewed conflict, the defense ministry said.
Former colonial power Italy, which lies across the Mediterranean from Libya and has been a destination for migrants fleeing the chaos at home, was very worried by the turn of events, Italian Deputy Prime Minister Matteo Salvini said.
“We need to throw water on the fire, not petrol on the fire. I hope that people, acting out of economic or business self-interest, is not looking for a military solution, which would be devastating,” Salvini said.