US President Donald Trump has revoked the security clearance of former CIA director John Brennan, White House press secretary Sarah Huckabee Sanders announced, citing "the risk posed by his erratic conduct and behaviour."
Brennan has been a leading critic of Trump.
Trump is also reviewing security clearances of other former officials including former FBI director James Comey, Sanders said during a regular White House news briefing.
"First, at this point in my Administration, any benefits that senior officials might glean from consultations with Mr Brennan are now outweighed by the risk posed by his erratic conduct and behaviour," Trump said in a statement read by Sanders.
"Second, that conduct and behaviour has tested and far exceeded the limits of any professional courtesy that may have been due to him," Trump said. "Mr Brennan has a history that calls into question his objectivity and credibility."