When President Donald Trump casually shared highly classified intel with top Russian diplomats last week, National Security Adviser H.R. McMaster, who was in the room, did not immediately realize the significance of what Trump divulged, according to an NBC News report out Wednesday.

Citing an unnamed U.S. official with direct knowledge of the matter, NBC reported that McMaster “is not steeped in counterterrorism” and thus was not immediately aware of the importance of the information Trump gave to Russian Foreign Minister Sergei Lavrov and Russian Ambassador Sergey Kislyak.

The Washington Post first reported on Monday that Trump had shared with the top diplomats information regarding an Islamic State threat, which had been provided by an ally who did not authorize the United States to disclose it. White House counterterrorism adviser Tom Bossert contacted officials at the CIA and NSA after the meeting to try to prevent further damage, according to the report.

NBC News reported that Bossert wasn’t even in the meeting, and only learned of Trump’s remarks from notes that he read immediately after it concluded.

McMaster told reporters on Monday evening that the Washington Post story “as reported” was “false,” but Trump blew up that spin Tuesday in a pair of early-morning tweets admitting that he shared “facts” with Russian officials.

Speaking from the White House briefing room later Tuesday, McMaster did not deny that Trump shared classified information and confirmed that the CIA and NSA were indeed contacted out of an “overabundance of caution” following the meeting.

“If there was nothing the President shared that he shouldn’t have shared, why did they contact the NSA and CIA?” a reporter asked.

“I would say an overabundance of caution but I’m not sure,” McMaster replied. “I’ve not talked to him about that. About why he reached out.”