Republicans have described as "ransom payment" the Biden administration's transfer to Tehran of $6 billion in frozen Iranian funds in exchange for the release of five Americans detained in Iran.

Representative Mike McCaul, the Republican chair of the House Foreign Affairs Committee, said the transfer "creates a direct incentive for America's adversaries to conduct future hostage-taking."

"The administration is demonstrating weakness that only further endangers Americans and freedom-loving people around the world," he said.

The White House confirmed Monday it had signed off on the transfer of the fund, South Korea's payment for oil sold by Iran, which Seoul froze as per US sanctions on Tehran for its nuclear program.

The US State Department said the money transfer is "a critical step in securing the release of Siamak Namazi, a businessman arrested in 2015 and accused of spying, wildlife conservationist Morad Tahbaz, venture capitalist Emad Sharqi and two others who wished to remain anonymous.

"As we have said, no money is going to Iran directly and no taxpayer funds are being used. The funds held in South Korea are Iran's funds," the State Department spokesperson said.

The official IRNA news agency had reported that five Iranians will also be released from the US as part of the deal announced last month.

Iran foreign ministry spokesperson Nasser Kanani said Iran expects to have full access to its assets in the coming days. Once the funds are moved to an account in Qatar, the American prisoners fly out of Iran.

WITH AFP