An Iranian official said Monday airports in Britain, Germany and the United Arab Emirates had started to refuse to refuel passenger planes from Iran but the reports were denied in all three countries, AFP reported.
"Since last week, after the passing of the unilateral law by America and the sanctions against Iran, airports in England, Germany, the UAE have refused to give fuel to Iranian planes," said Mehdi Aliyari, secretary of the Iranian Airlines Union, quoted by ISNA news agency.
Their refusal has so far impacted Iran Air, the national carrier, and a leading private airline, Mahan Air, as both operate several flights to Europe, Aliyari said.
Heshmatollah Falahat-Pisheh, an MP and member of the Iranian parliament's committee on foreign policy and national security, warned of retaliatory action by Tehran, especially towards the United Arab Emirates.
"We should definitely do the same thing to the Emirates, Britain and Germany whose planes need to be refuelled in Iran," he told ISNA.
But in London, a British government spokesman said: "At present Her Majesty?s Government is not aware of any occasions when fuel has been refused in the UK."
And a Dubai airport spokesman said Iranian planes were still able to refuel. "Iranian planes travelling to and from Dubai through Dubai International Airport still enjoy the refueling service," he said.
The General Civil Aviation Authority which oversees the sector in the UAE, of which Dubai is a member, said it did not have information of any such ban on Iranian planes.
However, a source close to the aviation sector in the UAE told AFP there was a problem with an international fuel supplier.
"A servicing company which provides fueling at several airports around the world has refused to provide Iranian planes with fuel, including at UAE terminals," he said.
"The Iranian air operators have alternative sources for refueling at UAE airports," he added, requesting anonymity.
The German office of Iran Air appeared to dismiss the reports from Tehran.
"It is not correct," Mohammad Reza Rajabi, the head of the airline's operations in Germany, told AFP. Flights and fuelling services had continued without interruption in Germany.
The German transport ministry said in a statement that neither US nor United Nations sanctions covered the refuelling of Iranian passenger planes.
But a report in Tuesday's edition of the Financial Times Deutschland said oil giant BP had not renewed a contract to supply Iranian airlines with fuel after it had expired at the end of June.
"We won't comment on individual contracts with every airline," BP told the daily.
"But we respect, in all the countries where we operate, the local rules regarding sanctions."
Last Thursday, US President Barack Obama signed into law the toughest ever US sanctions on Iran, which he said would strike at Tehran's capacity to finance its nuclear programme and deepen its isolation.
The measures, on top of new UN and European sanctions, aim to choke off Iran's access to imports of refined petroleum products like gasoline and jet fuel, and to curb its access to the international banking system.
On June 9, the UN Security Council imposed a fourth set of sanctions against Iran over its nuclear programme, followed by unilateral punitive measures by the European Union and later by the United States.
World powers led by Washington suspect Tehran is making nuclear weapons under the guise of a civilian atomic programme. Iran says its nuclear programme is purely for peaceful purposes.