CIA knew of Russia's help to Trump in US election in summer: Report

The Central Intelligence Agency (CIA) had evidence that Russia was interfering in the 2016 US election to boost Donald Trump earlier than previously thought, a media report has said.

Russia's interference was not made public until months after Trump's November 8 election victory, with US intelligence chiefs openly accusing Russian President Vladimir Putin of masterminding a hacking and disinformation campaign to skew the election results.

Citing former government officials, the New York Times report on Thursday said secret briefings much earlier in the presidential campaign had revealed Russia's move to support Trump — as well as divergence between the CIA and the Federal Bureau of Investigation (FBI), which is in charge of counterintelligence.

FBI senior officials had held that Russian hacks of Democratic Party communications were aimed at disrupting the election, without the specific goal of electing Trump. The agency later reached the same conclusion as the CIA.

John Brennan, the former head of the CIA, began in August secretly briefing top members of Congress on early, CIA-detected signs of possible collusion between Trump's inner circle and the Russians.

The FBI confirmed in March that it was probing whether Trump campaign aides had worked with the Russian effort to influence the election.

Two congressional intelligence committees have also launched investigations into the allegations.

Trump has vehemently denied accusations of collusion, and so far no evidence has publicly surfaced.