Saudi Aramco said a minor pipeline fire broke out but was quickly put out with no injuries or impact on oil supply.
"Minor pipeline fire this morning near Ras Tanura was quickly extinguished and repairs completed," said state oil company Aramco.
"No injuries and no impact on oil supply to our customers," it said. "Cause of incident under review."
Ras Tanura is in the east of Saudi Arabia, the world's largest oil exporter. The kingdom's biggest oil refinery is located there, and the port is a major oil operations centre.