Libya's eastern port of Hariga reopened on Wednesday after security guards ended a strike over salary payments, and a tanker has started lifting about 700,000 barrels of crude, an oil official said.
The guards had staged the strike on Tuesday, the latest in a series of such walkouts.
"The port management persuaded the guards to end the strike," the official said, asking not to be named.
OPEC producer Libya has managed to boost output to almost 600,000 barrels per day (bpd) by reopening two western fields and keeping eastern ports open despite militant attacks and fighting between factions allied to two rival governments.
But the oil sector is facing uncertainty. The internationally recognised government based in the east has unveiled plans to sell oil via a new state firm, bypassing the established entity in the capital Tripoli.