Libya's unity government said Monday its forces had seized two coastal cities between Tripoli and the Tunisian border from troops backing military commander Khalifa Haftar.

"Our forces took control of Sorman and Sabratha and are pursuing (Haftar's forces)," said a statement by Mohammed Gnunu, spokesman for the forces of the United Nations-recognised Government of National Accord.

Control of war-torn Libya is largely divided between pro-GNA forces and those of eastern-based Haftar, who launched an offensive to try to capture the capital on April 4 last year.

On their Facebook page, GNA forces published images of Grad rocket launchers, 10 tanks and armoured vehicles they said they had captured in the cities, which had been controlled by Salafist militias allied with Haftar.

Mohammad al-Gammoudi, a GNA commander on the ground, said Sorman and Sabratha had been seized after "six hours of fighting with air cover".

GNA chief Fayez al-Sarraj also said his forces had taken the cities.

Haftar's forces did not immediately comment.

Libya has suffered almost a decade of conflict since longtime dictator Moamer Kadhafi was brought down and killed in a 2011 uprising backed by several Western powers.

Russia, Turkey, the United Arab Emirates and others have fuelled fighting in the oil-rich but impoverished North African country.

The UN says hundreds have been killed and over 200,000 displaced since Haftar launched his battle for Tripoli.

Several UN-backed attempts to reach a ceasefire have failed and the UN has slammed repeated violations of a 2011 weapons embargo.

On March 17, the world body and nine countries called on Libya's warring parties to cease hostilities to allow health authorities to fight against the new coronavirus.