Washington on Sunday dismissed as false a claim by Tehran's foreign minister that the US and Iran had made a deal to exchange prisoners.
Iran's Foreign Minister Hossein Amirabdollahian told state TV earlier that a deal had recently been brokered and a prisoner exchange would happen within a “short period”.
“On our part everything is ready, while the US is currently working on the final technical co-ordination”, Mr Amirabdollahian said, according to Reuters.
But both the US State Department and the White House National Security Council (NSC) denied the claim.
“Statements from Iranian officials that a deal regarding the exchange of prisoners has been reached are another especially cruel lie that only adds to the suffering of their families”, State Department spokesman Ned Price said.
The NSC also said the claim of a deal was “false”, noting it had “nothing to announce at this time”.
Iran's claim comes after a remarkable interview last week in which Siamak Namazi, a businessman with dual US-Iranian citizenship, spoke by phone to CNN's Christiane Amanpour from inside Iran's notorious Evin prison.
“I desperately need President [Joe] Biden to finally hear us out, to finally hear our cry for help and bring us home”, he said.
Mr Namazi in January went on hunger strike to bring attention to his plight. His interview came less than a week after he joined two other detained Americans — Emad Shargi, a businessman, and Morad Tahbaz, a conservationist — and wrote a letter to Mr Biden, pleading for help.
Mr Namazi's father, Baquer Namazi, was released on medical grounds in October after more than six years in detention.
Mr Namazi was sentenced in 2016 to 10 years in prison, accused of spying and co-operating with the US government. Other prisoners are US-Iranian businessman Emad Sharghi and Iranian-American environmentalist Morad Tahbaz, who also holds British citizenship.
“Unfortunately, Iranian officials will not hesitate to make things up, and the latest cruel claim will cause more heartache for the families of Siamak Namazi, Emad Shargi, and Morad Tahbaz”, an NSC representative said.
“We remain committed to securing the freedom of Siamak, Emad, and Morad, but we have nothing to announce at this time.”
Tehran has for years sought the release of more than two dozen Iranians or Iranian-American citizens held in the US under various convictions.
Iran, which holds dozens of Iranian dual nationals and foreigners, has been accused by rights activists of arresting them to try to extract concessions from other countries, which it denies.
On Friday, Saudi Arabia and Iran reached an agreement to resume diplomatic relations, in a historic deal brokered by China.