"At the moment the volume of Iran's strategic petrol supplies has increased by over a billion litres," Nooreddin Shahnazi-Zadeh, the head of National Iranian Oil Refining and Distribution Company told Mehr news agency without specifying the total stockpile.
Shahnazi-Zadeh dismissed the threat of sanctions, saying "it is impossible to impose such limitations in the current situation."
Oil-rich Iran, OPEC's second largest oil exporter, is dependent on petrol imports to meet over one third of its domestic consumption, which is about 65 million litres a day, due to shortage of refining capacity.
Shahnazi-Zadeh said the output of Iranian refineries was about 44.6 million litres a day which would increase to 45.6 in the current Iranian year to March 2011.
Western countries led by Washington have stepped up global efforts to secure a fourth round of UN sanctions against Iran for pursuing its sensitive uranium enrichment programme.
Among measures mentioned by top Western officials are restrictions on fuel to the Islamic republic, which announced last November it would launch an emergency petrol production plan in a bid to dodge such punitive measures.
