A Defense Ministry official says Libya's navy has prevented a Malta-flagged oil tanker from entering its territorial waters apparently en route to a militia that has shut down oil terminals for months in a challenge to the government.

Spokesman Abdul-Razak al-Shabahi told The Associated Press on Monday that the tanker tried to enter the northeastern city of Misrata's port the previous night. He says the tanker and its cargo were not meant for the government.

Libya's eastern militia is demanding more autonomy from the government in Tripoli and a share of oil revenues. Last summer, its fighters shut down most of the country's terminals and mediation has failed.

The government has threatened to use force if the militia attempts to bring in oil before the standoff is resolved.