DUBAI, Aug 21 (Reuters) - The process of releasing U.S. prisoners held in Iran will take up to two months, Iran's Foreign Ministry Spokesperson Nasser Kanaani said on Monday during a press conference.

"A specific time frame has been announced by relevant authorities, and it will take a maximum of two months for this process to take place," Kanaani said.

Earlier this month, Tehran and Washington reached an agreement whereby five U.S. citizens held in Iran would be freed while $6bn of Iranian assets frozen in South Korea would be released.