US President Donald Trump is considering revoking security clearances for ex-CIA Director John Brennan and other Obama-era critics of his administration.
The White House named six former intelligence, law enforcement and national security chiefs.
Press secretary Sarah Sanders said they had "politicised and in some cases monetised their public service" to make "baseless accusations" about Mr Trump.
They include former FBI Director James Comey, whom the president fired.
In the daily news conference, Mrs Sanders also targeted former Director of National Intelligence National James Clapper, former National Security Adviser Susan Rice, former National Security Agency Director Michael Hayden and former FBI Deputy Director Andrew McCabe.
Mrs Sanders denied a reporter's suggestion that the president wanted to punish the former officials for free speech.
The press secretary said Mr Trump "doesn't like the fact that people are politicising agencies and departments that are specifically meant to not be political and to be monetised off security clearances".
She said security clearance "provides inappropriate legitimacy to accusations with zero evidence".
After Mr Trump gave credence following his Helsinki summit to Putin's denials about Russian meddling in the 2016 US election despite findings by the American intelligence community, Mr Brennan called the president's remarks "nothing short of treasonous."
In his Twitter post last week, Mr Brennan stated, "Not only were Trump's comments imbecilic, he is wholly in the pocket of Putin."
Donald Trump’s press conference performance in Helsinki rises to & exceeds the threshold of “high crimes & misdemeanors.” It was nothing short of treasonous. Not only were Trump’s comments imbecilic, he is wholly in the pocket of Putin. Republican Patriots: Where are you???— John O. Brennan (@JohnBrennan) July 16, 2018
"Accusing the president of the United States of treasonous activity when you have the highest level of security clearance, when you're the person that holds the nation's deepest, most sacred secrets at your hands and you go out and you make false accusations against the president of the United States, he [the president] thinks that is something to be very concerned with. And we're exploring what those options are and what that looks like," Mrs Sanders said.
Asked if Trump was punishing the former officials because of their criticism, Mrs Sanders said, "No, I think you are creating your own story there."
Mr Clapper told CNN the plan was "a very, very petty thing to do".
"There is a formal process for doing this, but you know I guess legally the president has that prerogative," Clapper said on CNN.
"He can suspend or revoke clearances as he sees fit, and if he chooses to do it for political reasons, well I think that's a terrible precedent. And it's a very sad commentary. And it's an abuse of the system."
Many former US officials retain their security clearances after they leave government service because they continue to advise their former agencies or because it is a condition of employment as government contractors or consultants.
The CIA did not immediately comment on the White House threat.
-Reuters / BBC