Iran’s top diplomat claimed on Sunday that a prisoner swap was near with the US, though he offered no evidence to support his assertion. American officials did not immediately respond to requests for comment about his remarks.

Iranian Foreign Minister Hossein Amirabdollahian has made similar comments in the past about possible deals with the US on frozen assets abroad and other issues that never came to fruition.

Some of those remarks have appeared aimed at shoring up domestic support amid the mass protests challenging Iran’s theocracy and supporting the country's troubled rial currency. However, in an interview on Sunday with Iranian state television, Amirabdollahian claimed that Iran had “reached an agreement in recent days regarding the exchange of prisoners between Iran and the United States.”

“If everything goes well on the American's side, I think we will see the exchange of prisoners in the short term,” he added.

He alleged a document between Iran and the US laying out the exchange had been “indirectly signed and approved” since March 2022.

The US State Department and the White House did not immediately respond to requests for comment Sunday from The Associated Press.

Iran long has taken prisoners with Western passports or ties to use in negotiations with foreign nations.

As of right now, there are at least four American citizens known to be held in Iranian prisons on widely disputed espionage charges.The evidence against them has never been made public.

The detainees all have dual US-Iranian citizenship, something Tehran does not recognize. In recent days, however, longtime Iranian-American detainee Siamak Namazi was allowed to conduct an interview with CNN from Tehran's notorious Evin prison — something that would not have happened without the acquiescence of security forces.

Meanwhile, Ali Bagheri Kani, a deputy Iranian foreign minister who has handled nuclear talks with world powers, made a trip Sunday to Oman, a longtime interlocutor between Tehran and Washington.