Libya's eastern oil export port Hariga shut down due to a strike of security guards, a port official said on Sunday.
Hariga in Tobruk was the last functioning export port apart from two offshore fields. It used to export around 120,000 barrels a day.
Only Brega port is still open but it is used to supply the Zawiya refinery with crude.
All other ports and most oilfields have shut down due to fighting nearby or pipeline blockages.