Tuesday's unexplained blast along the Kirkuk-Ceyhan link in southern Turkey contributed to a rise in international crude oil prices to a seven-year high.

The pipeline normally carries more than 450,000 barrels a day from oil fields in northern Iraq to a Turkish port on the Mediterranean Sea.

Turkey's sate oil operator Botas said the fire had been fully extinguished late Tuesday but gave no indication for what caused the blast.

It said early on Wednesday that "all the necessary precautions have been taken" and oil flows would resume later in the day.

The blast occurred in wintery weather conditions in a sparsely populated region of southern Turkey.

Images on social media showed huge fireballs illuminating the night sky in snow-covered fields.

Local officials said the blast also halted traffic along a highway linking the southern cities of Adana and Gaziantep.