US needs to prove it's serious on prisoner swap: Iran FM Zarif

Iran's Foreign Minister Mohammad Javad Zarif on Saturday said that the United States needs to prove its seriousness on prisoner exchange before the two countries can begin negotiations.

Zarif made the comment in an interview with CBS's 'Face the Nation' show where host Margaret Brennan asked him whether he would, "as a show of...seriousness" release some of the at least five Americans who are incarcerated in Iran.

On Wednesday, the Foreign Minister, in a diplomatic overture amid a worsening relationship with Washington, publicly proposed to negotiate a prisoner exchange between the two countries, saying he had been authorised to conduct such talks.

During the interview, Zarif said that many Iranians are imprisoned in the US for violating sanctions, adding that the Trump administration already aware of which prisoners Iran would like in return for American prisoners in Iran being released.

"I am responsible for foreign policy. I'm not responsible for interfering in court's decisions. I can intervene when there is an exchange, an offer of exchange. I cannot intervene as foreign minister," Zarif was quoted as saying.

However, Zarif denied that Americans imprisoned in Iran were being mistreated.

He claimed that Iran had made an offer six months ago to Washington to discuss the status of the prisoners but it went unanswered.

He said, "I can intervene as a private individual on humanitarian basis, and I do, I do," adding, "But as foreign minister, I do not have a standing in any Iranian court unless I can engage in an exchange with Iranians who are wrongful, in our view, detained either inside the United States or elsewhere."

Meanwhile, a US State Department spokesperson told The Hill in a statement on Saturday that Iran can show it is serious by releasing "innocent US persons."

"The Iranian regime can demonstrate its seriousness regarding consular issues, including Iranians who have been indicted or convicted of criminal violations of US sanctions laws, by releasing innocent U.S. persons immediately," the spokesperson said.

"We call on Iran to free all unjustly detained and missing U.S. persons, including Xiyue Wang, Robert Levinson, Siamak Namazi, and Nizar Zakka, among others," he added.

Tension between Iran and the United States have heightened recently after the Trump administration designated Iran's elite Revolutionary Guard Corps (IRGC) as a foreign terrorist organisation. This is the first time when the US has designated any foreign country's military as terrorists.

In addition, the US has also threatened to sanction other countries who purchase Iranian oil, including India and China, starting from May 2, to which Iran has likely retaliated.

"I have enough responsibility on my shoulders to prevent a war, to try to circumvent the U.S. attempts to prevent Iran from engaging in what is legally ours, and that is normal economic relations," Zarif said.

"So, I do this as a part of my job, as foreign minister to exchange people without attribution of guilt. Simply to make it possible for people to go back home," the Foreign Minister was quoted as saying.