Libyan government forces have seized a tanker that had loaded crude at a port under the control of rebels who plan to sell oil independently of the Tripoli government.
The North Korea-flagged shipped was being escorted to western Libya, a spokesman for the state-owned National Oil Corp Mohammed El-Harari told Reuters, confirming Libyan media reports.
Another Libyan official, Abdelwahab al-Qaim told Reuters: "The ship has been seized by government forces. There are no damages to the ship."
A rebel spokesman had earlier denied they had lost control of the ship.
More top news
One of four men accused of plotting to use a moped in a series of drive-by shootings in London has changed his plea at the Old Bailey.
The North Yorkshire town was divided since the historic bridge was damaged by floods at Christmas.
Syrian President Bashar al-Assad has vowed to regain control of the entire country but warned it could "take a long time".