The State Department admitted Thursday that a controversial $400 million payment the United States made to Iran in January was used as "leverage" in the release of American hostages.
"We returned to Iran its $400 million dollars … with concerns that Iran may renege on the prisoner release," State Department spokesman John Kirby told reporters. "We, of course, sought to maintain maximum leverage until after American citizens were released. That was our top priority."
The administration has faced mounting criticism that the payment was for ransom.
Officials have for weeks denied that the cash transfer, which occurred around the same time that Iran released three American hostages, was quid pro quo, and have instead said that the timing of the payment was "coincidental."
After it was revealed Wednesday that the U.S. delayed delivering the $400 million to Iran until the American hostages were "wheels up," the State Department relented.
"The payment of the $400 million was not done until after the prisoners were released. I'm not disputing that," Kirby said.
He told reporters that the cash transfer was contingent upon the prisoner release, but denied that the exchange was a quid pro quo since the Iranians "were going to get this money, anyway."
"The events came together simultaneously," Kirby said. "It would have been foolish, imprudent, irresponsible for us not to try to maintain maximum leverage."
Officials have for months refused to discuss details of the payment with reporters and lawmakers, including the timing of it and how it was made.
President Barack Obama, Secretary of State John Kerry, and former Secretary of State Hillary Clinton have called the payment old news.
They have said that the $400 million payment was the first installment of a $1.7 billion legal settlement with the Islamic Republic for a decades-old arms deal gone awry, an effort that was separate from the prisoner talks.
"So far as I know it had nothing to do with any kind of hostage swap, or any other tit-for-tat," Clinton said in early August.
The administration has since delivered another $1.3 billion to Iran. Officials have repeatedly disregarded the notion that Iran would receive a "windfall" of cash in the aftermath of the Iran deal.