The explosion in the eastern Agri province occurred as a result of "an attack by the separatist terrorist organisation," Governor Ali Yerlikaya said in a statement carried by the Anatolia news agency, referring to the outlawed Kurdistan Workers' Party (PKK).

Last month, the rebels were held responsible for blowing up another section of the pipeline in the same province, which borders Iran.

An official from Turkey's state gas and oil company BOTAS told AFP Wednesday that the blaze at the pipeline had been extinguished and repair work was already under way.

She ruled out a supply shortage. Turkey imports natural gas also via pipelines from Russia and Azerbaijan.

The authorities have also blamed the PKK for two bomb attacks that hit a pipeline carrying oil from Iraq in the past two months.

The PKK, fighting for autonomy in the Kurdish-majority southeast, said on August 13 it was declaring a truce until September 20, a period that covers the Muslim holy month of Ramadan and a September 12 referendum on constitutional changes.

Ankara has dismissed similar truces in the past and continued to fight the rebels.

The PKK, listed as a terrorist group by Turkey and much of the international community, took up arms in 1984, sparking a conflict that has claimed some 45,000 lives.