A newspaper report says Chinese state companies are supplying gasoline to Iran, a development that could undermine U.S. efforts to pressure Tehran to give up its nuclear program.
London's Financial Times reports Wednesday the companies are selling the petrol through intermediaries, and provide up to a third of Tehran's gasoline imports.
The report is based on unnamed oil traders and bankers.
The sales would complicate U.S.-led efforts to isolate the Iranian government with tough economic sanctions.
Fuel sales to Iran currently are legal. U.S. officials have suggested imposing international sanctions on the trade to force Iran to stop its nuclear activities.
Western countries accuse Iran of secretly trying to build a nuclear weapon, which Tehran denies.
Envoys from the world's major powers will discuss the situation Wednesday outside the U.N. General Assembly in New York.
The envoys from the U.S., Britain, France, Russia, China and Germany are preparing for an October 1 meeting with Iranian officials in Geneva.
On Tuesday, Iranian President Mahmoud Ahmadinejad called for global nuclear disarmament. He said nuclear weapons are the source of threats and instability.
He told the Associated Press that Tehran will not seek to avoid discussion on the nuclear issue. But he said it will only pursue talks through the International Atomic Energy Agency.
Also Tuesday, Iran's nuclear energy chief Ali Akbar Salehi announced that the country has built new centrifuges he says are better able to enrich uranium, a key ingredient in nuclear weapons.
Some information for this report was provided by AFP and Reuters.