The closures underscore the new Libyan government's complex task in reviving oil production, which has been battered by strikes, protests and Islamist militant attacks since the fall of Muammar Gaddafi in the 2011 uprising.

Commander Mohammad Ahmad Alkhbasha told Reuters the Petroleum Facilities Guards' southern brigade had shut the Gulf field and the Al Wafa field, which usually produces around 30,000 barrels per day of light oil condensate.

Al