The Obama administration hasn't given up trying to secure the release of Robert Levinson, Kerry said on ABC's "This Week."
"To suggest that we've abandoned him, or anybody has abandoned him, is simply incorrect and not helpful," Kerry said. "The fact is that I have personally raised the issue not only at the highest level that I have been involved with but also through other intermediaries."
But Iranian Foreign Minister Mohammad Javad Zarif, interviewed on CBS's "Face the Nation," said that Iran's government does not know where Levinson is.
"We know that he is not incarcerated in Iran," Zarif said. "If he is, he is not incarcerated by the government. And I believe the government runs, pretty much, good control of the country."
Kerry said the U.S. thinks Iran "has the ability to help us here."
"We're looking for proof of life," Kerry said. "We're working on several processes that I'm not free to talk about, but there are a number of different channels that are being worked, and they're being worked aggressively."
Zarif offered a noncommittal response. "If we can trace him and find him, we will certainly discuss this," he said. "Everything is possible. But I'm saying that we have no trace of him in Iran."
A video and photographs of Levinson that were sent to his family several years ago appeared to have come from Pakistan, but U.S. officials have never been able to establish whether he was being held there or in Iran or in some other country. At this point, some officials believe Levinson, who was in poor health, has most likely died.
According to articles published in recent days by the Associated Press, the Washington Post and the New York Times, Levinson worked as a CIA contractor for several years after retiring from the FBI. He reported to officials in the analysis division, who do not have authority to run intelligence gathering operations. His chief contact at the agency knew in advance of his trip to Iran, the articles say.
After Levinson disappeared, CIA officials initially told Congress that he had not been working for them. Senior officials at the agency discovered what had happened only after people close to Levinson contacted members of Congress with evidence of his ties to the CIA. Eventually, several agency officials were forced to resign over the affair, all of which remained secret until this week.
"The CIA did not tell the truth to the American Congress about Mr. Levinson," Sen. John McCain said Sunday on CNN's "State of the Union."
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