Congress was not informed in advance about the swap for Army Sgt. Bowe Bergdahl because the Taliban threatened to kill him if it leaked, three congressional officials told The Associated Press on Thursday.
Obama administration officials told senators in a classified briefing a day earlier that the threat motivated President Obama to authorize the deal quickly.
Sen. Angus King (I-Maine), who attended the closed-door briefing, alluded to the threat Thursday morning on CNN’s “New Day.”
“I pressed in the hearing on opening some of this information up,” he said. “They had intelligence that, had even the fact of these discussions leaked out, there was a reasonable chance Bowe Bergdahl would have been killed. And that was one of the pieces of information that we learned yesterday that gave it some credence in terms of why it had to be kept quiet so long.”
Administration officials previously have said they kept the deal a secret because of worries it could have fallen apart. They have also pointed to Bergdahl's deteriorating heath in defending the decision to swap five prisoners held at Guantanamo Bay, Cuba, for the American soldier.
On Thursday, a senior administration official said a video of Bergdahl the administration received in January added more urgency to getting him back. The official also said that senators were told that apart from his deteriorating health, "we had both specific and general indications that Sgt Bergdahl 's recovery — and potentially his life — could be jeopardized if the detainee exchange proceedings were disclosed or derailed.”
The swap has created a firestorm on Capitol Hill, with lawmakers upset they weren't consulted.
The administration is required under law to notify Congress 30 days before releasing detainees at Guantanamo Bay, though the administration has argued that requirement is unconstitutional. Obama signaled his difference with the requirement in a signing statement when the 2014 National Defense Authorization Act became law.
Critics have also argued the administration gave up too much for Bergdahl, who is accused of abandoning his position by walking off his post. And they worry the released detainees will return to the battlefield.
Senators who emerged from the briefing said they weren't sold on the reasons to circumvent Congress in executing the agreement.
This story was updated at 2:47 p.m.