The surprise development on Friday followed multiple visits by top foreign diplomats to Libya in recent weeks, and came after a series of agreements and pledges that, however, have failed to be implemented.

EU diplomatic chief Josep Borrell described it as a "constructive first step forward".

The announcement "demonstrates the determination of the Libyan leaders to overcome the current stalemate and creates a new hope for a common ground towards a peaceful political solution to the longstanding Libyan crisis and the termination of all foreign interference throughout the country", he said.

He urged "concrete actions" to enable a permanent ceasefire and a relaunch of the political process, requiring "the departure of all foreign fighters and mercenaries present in Libya" as well as the resumption of peace negotiations "in the framework of the UN-led Berlin process."

Borrell also called on all Libyan parties to implementat economic reform "with a view to agreeing on a fair and transparent distribution mechanism for oil revenues and to enhancing the governance of Libyan economic and financial institutions."

Libya has been torn by violence since the 2011 toppling and killing of longtime dictator Moamer Kadhafi in a NATO-backed uprising.