WASHINGTON Five U.S. citizens detained in Iran, who are expected to be swapped for five Iranians imprisoned in the United States as early as next week, are "in full health," Iranian President Ebrahim Raisi said in a television interview on Tuesday.

"They are very healthy and, according to our latest information, they are in full health," Raisi told Lester Holt of NBC Nightly News in an interview taped in Tehran on Tuesday, the U.S. television network said.

The five U.S. citizens expected to be released include Siamak Namazi, 51, and Emad Sharqi, 59, as well as environmentalist Morad Tahbaz, 67, who also holds British nationality, the U.S. administration has said.

The identities of the fourth and fifth Americans have not been disclosed.

As part of the prisoner swap deal first made public on Aug. 10, the United States has agreed to the transfer of $6 billion in Iranian funds from South Korean to Qatari accounts, where they can be spent only on humanitarian goods.

Allowing the five to leave Iran would remove a major irritant between Washington and Tehran, which remain at odds on issues from the Iranian nuclear program to Tehran's support for regional Shi'ite militias.

The prisoner exchange could take place as early as next week according to eight Iranian and other sources familiar with the deal, negotiated in indirect U.S.-Iran talks mediated by Qatar. One source familiar with the talks has previously said the Swiss embassy, which represents U.S. interests in Iran, had visited the five Americans and said they were in good health.

"The arrangements have been done and the final action of swapping the prisoners should be finalized in the due time," Raisi told NBC according to excerpts released by the network without specifying a date.

While Raisi appeared to acknowledge the $6 billion may only be used for humanitarian purposes, he said Iran would decide how the money would be spent.

"This money belongs to the Iranian people, the Iranian government, so the Islamic Republic of Iran will decide what to do with this money," Raisi said in the interview, speaking through an Iranian government translator.

Asked if the money would be used for other purposes apart from humanitarian needs, Raisi said: "Humanitarian means whatever the Iranian people needs, so this money will be budgeted for those needs and the needs of the Iranian people will be decided and determined by the Iranian government."

The U.S. State Department has stressed the money is going from restricted accounts in South Korea to restricted accounts in Qatar and that the United States will have oversight as to how and when these funds are used.

(Reporting By Arshad Mohammed in Washington; Additional reporting by Samia Nakhoul in Dubai; editing by Timothy Gardner)