Libya's National Oil Company, NOC, announced in recent days that it has halted operations at two major oil terminals closing several fields.
Daily ouput has been halved at a time when "oil and gas prices are soaring" under the impact of the war in Ukraine, according to the NOC.
At the centre of the crisis is the dispute between the parliament sitting in Tobrouk in the east and led by Fathi Bachagha and the incumbent executive of Abdelhamid Dbeibah in Tripoli.
On Tuesday, Dbeibah reaffirmed that he would only hand over power to an elected government.
Armed groups close to the parliament in the east are calling for power to be transferred to the new prime-minister, Fathi Bachagha.
Mercenaries from private company Wagner with links to the Kremlin also support the armed groups behind the new prime-minister.
On Tuesday, US Ambassador in Libya, Richard Norland, warned in a meeting with the Libyan central bank governor against using oil revenues "for partisan political purposes".