TEHRAN Iranian media reported on Sunday that their country's military had shot down a U.S. reconnaissance drone in eastern Iran, but a U.S. official said there was no indication the aircraft had been shot down.
NATO's U.S.-led mission in neighbouring Afghanistan said the Iranian report could refer to an unarmed U.S. spy drone that went missing there last week.
The incident comes at a time when Tehran is trying to contain foreign outrage at the storming of the British embassy on Tuesday, after London announced sanctions on Iran's central bank in connection with Iran's nuclear enrichment programme.
Iran has announced several times in the past that it shot down U.S., Israeli or British drones, in incidents that did not provoke high-profile responses.
"Iran's military has downed an intruding RQ-170 American drone in eastern Iran," Iran's Arabic-language Al Alam state television network quoted a military source as saying.
"The spy drone, which has been downed with little damage, was seized by the Iranian armed forces," the source said. "The Iranian military's response to the American spy drone's violation of our airspace will not be limited to Iran's borders."
Iranian officials were not available to comment further.
NATO's International Security Assistance Force in Afghanistan said in a statement: "The UAV (unmanned aerial vehicle) to which the Iranians are referring may be a U.S. unarmed reconnaissance aircraft that had been flying a mission over western Afghanistan late last week.
"The operators of the UAV lost control of the aircraft and had been working to determine its status."
A U.S. official, who asked not to be named, said: "There is absolutely no indication up to this point that Iranians shot down this drone."
Tuesday's storming of the British embassy attracted swift condemnation from around the world, further isolating Iran.
Britain evacuated its diplomatic staff from Tehran and expelled Iranian diplomats from London in retaliation. Several other EU members like Germany, France and Spain also recalled their ambassadors from Tehran.
The United States and Israel have not ruled out military action against Iran's nuclear facilities if diplomacy fails to resolve a dispute over a programme they suspect is aimed at developing atomic weapons. Iran says it would respond to any strike by attacking Israel and U.S. interests in the Gulf.
In January Iran said it shot down two unmanned Western reconnaissance drones in the Gulf. In July Iran said it had shot down an unmanned U.S. spy plane over the holy city of Qom, near its Fordu nuclear site.
Western nations on Thursday significantly tightened sanctions against Iran, with the European Union expanding an Iranian blacklist and the U.S. Senate passing a measure that could severely disrupt Iran's oil income.
Iran warned the West on Sunday any move to block its oil exports would more than double crude prices with devastating consequences on a fragile global economy.
"As soon as such an issue is raised seriously the oil price would soar to above $250 a barrel," Foreign Ministry spokesman Ramin Mehmanparast told the Sharq newspaper.
So far neither Washington nor Brussels has finalised a move against Iran's oil trade or its central bank. Crude prices were pushed up over the British embassy storming with ICE Brent January crude up 95 cents on Friday to settle at $109.94 a barrel.
(Additional reporting by Ramin Mostafavi in Tehran, Caren Bohan and David Alexander in Washington and Missy Ryan in Bonn; Writing by Parisa Hafezi; Editing by Peter Graff)