Donald Trump took to Twitter on Sunday (15 January) night to accuse outgoing CIA director John Brennan of being "the leaker of fake news" after he criticised the President-elect in an interview earlier in the day.

Brennan said Trump should be more "disciplined" in his remarks and that he does not think the incoming leader has a "full appreciation" of the threat Russia could pose around the world in an interview with Fox News Sunday.

Trump quoted the title of a Fox News article on the interview, saying "Outgoing CIA Chief, John Brennan, blasts Pres-Elect Trump on Russia threat. Does not fully understand." He then added: "Oh really, couldn't do much worse - just look at Syria (red line), Crimea, Ukraine and the build-up of Russian nukes. Not good!" Before going on to ask: "Was this the leaker of Fake News?"

The outgoing head of the CIA had also criticised Trump's brash remarks, particularly on Twitter, saying: "Spontaneity is not something that protects national security interests."

The relationship between Trump and the US intelligence community has been tense since Trump's initial rejection and grudging acceptance of their conclusion that Russia attempted to influence the US election to help him become president.

Trump and his team had called the claims "ridiculous" but have lately admitted that they now think Russia was behind the hacking of the Democratic National Committee.

In a press conference on Wednesday 11 January, Trump lambasted the intelligence services, saying they had "allowed" out the unverified dossier that alleged Russia has "compromising material" on Trump. "That's something that Nazi Germany would have done, and did do," Trump said.

Brennan called the equation of the intelligence community with Nazi Germany "outrageous", saying he took "umbrage" at the remarks.

Trump also invoked "fake news" during last week's press conference. During a heated exchange with CNN reporter Jim Acosta, he pointed at Acosta and said "You are fake news!" after refusing to take a question from him.