The Iranian Intelligence Ministry said at a press conference on Monday that it had identified and arrested 17 spies acting on behalf of the US Central Intelligence Agency (CIA).
The alleged spies were all Iranian citizens, officials said, trained by CIA officers to collect classified information and transmit that information from inside Iran. The spies received fake identification papers from the CIA, an Iranian spokesperson said.
US President Donald Trump responded to the allegations on Twitter, stating that they were "totally false".
Officials claimed that some of the Iranian citizens acting as spies for the CIA had been lured into spying in order to receive a US visa or even a job in the United States.
Tehran has made similar claims in the past and it was not immediately possible to determine whether the claims are legitimate.
The alleged spies were handed over to the judiciary. Some of the spies will be executed, while others decided to cooperate with Iran to work against the Americans, an Iranian official said at the press conference.
The US State Department did not immediately respond to Euronews' request for comment.
The CIA does not acknowledge overseas recruitment, according to NBC News.
The announcement, delivered at an intelligence ministry press conference, came amidst increased tensions between Iran and the United States along with its allies.
Iran seized a British-flagged tanker in the Strait of Hormuz on Friday. On Monday, British Prime Minister Theresa May held an emergency government meeting concerning the country's actions.
Trump said the US had shot down an Iranian drone on Thursday, which Iran's deputy foreign ministry denied.
US President Donald Trump issued economic sanctions on Iran last month as part of a "maximum pressure" campaign against the nation. Trump had previously withdrawn from the 2015 Iran nuclear deal crafted to limit Iran's nuclear programme in exchange for the lifting of crippling economic sanctions.
The Iranian foreign minister said over the weekend that US sanctions were a form of "economic terrorism".