In a statement on Saturday, the EU's High Representative for Foreign Affairs and Security Policy Josep Borrell said the mutual gesture is a "constructive first step forward" that shows the determination of the Libyan leaders to overcome the stalemate and creates hope for ending the longstanding conflict, reports Xinhua news agency.

"We fully support the agreement around the principles to immediately cease all military activities across Libya, requiring the departure of all foreign fighters and mercenaries present in Libya, and resume the negotiating process in the framework of the UN-led Berlin process," he said in a statement.

Borrell urged all concerned parties to translate the principles into concrete actions on the ground leading to a permanent ceasefire.

Serraj and Saleh on Friday issued statements announcing the ceasefire, as well as calling for a resumption of oil exports and elections in the country.

Serraj's UN-backed government had been engaged in a deadly armed conflict against the eastern-based army, which is allied with the eastern-based House of Representatives, for more than a year over control of the capital Tripoli, before his government recently took over all western Libya.

Libya has been in a civil war since its leader Muammar Gaddafi was ousted and killed in 2011.

The eastern-based army and the UN-backed government were engaged in a deadly armed conflict for more than a year over the control of capital Tripoli before the UN-backed government announced taking over all of western Libya following the eastern-based army's withdrawal from the region.

After the eastern-based army withdrew from western Libya, the UN-backed government has been trying to take control of the city of Sirte and Jufra district tn the country's central region.