DOHA/NEW YORK: Five US citizens left Iran and landed in Doha on Monday in a prisoner swap for five Iranians held in the United States and the transfer of $6 billion in Iranian funds, marking a rare moment of cooperation between the long-time antagonists.

“Today, five innocent Americans who were imprisoned in Iran are finally coming home,” US President Joe Biden said in a statement shortly before the US detainees descended the stairs of a Qatari jet to be embraced by US diplomats.

Separately, Iran’s Press TV said the five Iranians held by the United States and charged with committing crimes had been freed, an apparent reference to their being granted clemency. Two arrived in Doha, US and Iranian officials said.

“This was purely a humanitarian action,” Iranian President Ebrahim Raisi said after arriving in New York for the annual UN General Assembly. “It can certainly be a step based upon which in the future other humanitarian actions can be taken.”

It was unclear whether the exchange might bring progress on the many issues that divide the two nations, including Iran’s nuclear program, its support for regional Shi’ite militias, the presence of US troops in the Gulf and US sanctions on Iran.

Relations between the United States and Iran, adversaries for more than 40 years, have been especially bitter since former US President Donald Trump in 2018 reneged on a deal to curb Iran’s nuclear program and reimposed US sanctions.

Washington suspects the program may aim to develop nuclear weapons - an ambition Tehran denies - that could threaten Israel or US Gulf Arab allies.

US Secretary of State Antony Blinken left the door open to diplomacy on the nuclear file, which he described as “perhaps the number one issue of concern,” but suggested nothing was imminent.