This article is more than 2 years old

This article is more than 2 years old

The Trump administration warned of a potential national security risk related to an opinion piece published last week in which an anonymous administration official declared he or she was working from the inside to subvert the president.

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“We’ll find out if there was criminal activity involved,” Vice-President Mike Pence told Fox News Sunday. “I think the president’s concern is that this individual may have responsibilities in the area of national security.”

Pence was echoed by the Trump adviser Kellyanne Conway, speaking on CNN’s State of the Union as the hunt for the author continued.

“There could be a national security risk at hand,” she warned. “It depends on what else has been divulged by this individual … Anybody who would do this, you don’t know what else they’re saying.”

The anonymous editorial was published on Wednesday by the New York Times and attributed to a “senior” administration official. It described a “two-track presidency” in which “many Trump appointees have vowed to do what we can to preserve our democratic institutions while thwarting Mr Trump’s more misguided impulses until he is out of office”.

Trump called the piece “treason”.

All cabinet members to have been asked about the piece have denied authorship.

On Sunday, Pence told CBS’s Face the Nation he was “100% confident that no one on the vice-president’s staff was involved in this anonymous editorial”. He also told Fox News Sunday he was not the author, would take a lie detector test on the matter “in a heartbeat”, and would “submit to any review the administration wanted to do”.

But the suggestion the piece represented a national security risk had not previously been aired. Speaking to Fox, Pence called the piece “deceitful” and said “it’s really an assault on our democracy”.

On Friday, Trump called on his attorney general, Jeff Sessions, to lead an investigation to identify the author. But Conway acknowledged that the opinion piece per se did not constitute criminal activity.

“I think this person is going to suss himself or herself out,” Conway said. “Cowards are like criminals, eventually they tell the wrong person.”

Play Video 1:06 Denials and accusations: anonymous NYT op-ed sparks frenzy – video

There is no evidence or indication apart from the Trump administration’s assertion that the author of the piece has a national security role. But it would not be unprecedented for a member of the national security team to buck the president, according to a book to be published on Tuesday by the veteran reporter Bob Woodward.

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The Guardian obtained a copy of the book, Fear. Woodward reports that the defense secretary, James Mattis, did not act on a Trump order to assassinate the Syrian president, Bashar al-Assad.

“We’re not going to do any of that,” Woodward quotes Mattis as telling an aide. “We’re going to be much more measured.”

Trump has claimed he would have liked to speak with Woodward for the book but was not asked to.

“I never got a call. I never got a message,” Trump told Woodward in a taped telephone call between the two that was published by the Washington Post this week. Woodward replied that he had requested an interview with the president through “about six people”, including Conway.

On Sunday, Conway told NBC’s Meet the Press she had not forwarded a request by Woodward to speak with Trump to the president.

“I didn’t bring the request to the president directly,” she said.