United States intelligence agencies have told The White House that they now have “high confidence” that the Russian government was involved in the cyberattack which resulted in 20,000 emails being leaked from the Democratic National Committee (DNC) - according to The New York Times.
The paper says that its reporting is based on “federal officials who have been briefed on the evidence.”
The emails - which indicated bias towards the Clinton campaign - were subsequently published by Wikileaks.
Donald Trump took to Twitter in the wake of the publication of the NYT article to accuse the newspaper of "pushing" a Democratic narrative linking Putin to a plot to release the documents to help his campaign.
Funny how the failing @nytimes is pushing Dems narrative that Russia is working for me because Putin said "Trump is a genius." America 1st!
— Donald J. Trump (@realDonaldTrump) July 27, 2016
Later at a press conference Mr Trump called on Russian hackers to target his opponent: "Russia, if you're listening, I hope you're able to find the 30,000 [Hillary Clinton] emails that are missing ... I think you will probably be rewarded mightily by our press. Let's see if that happens, that'll be nice," the Republican candidate said.
A briefing from US intelligence suggesting that Vladimir Putin’s Government was behind the attack would put US President Barrack Obama in a difficult position as a public accusation linking Russia to the leak would lead to an instant escalation in tensions between the two states.
When asked in an interview with NBC News if Russia was trying to manipulate the out come of the US election Mr Obama said that, “Anything is possible.”
He added that officials in Moscow regularly “try to influence elections in Europe.”
Hillary Clinton’s campaign manager, Robby Mook told CNN that he had been informed that Russia was behind the leak, and that it is part of an effort to damage Mrs Clinton’s campaign and to help the Republican Party to win the election in November.
History. pic.twitter.com/1ayWTx8SPH
— Hillary Clinton (@HillaryClinton) July 26, 2016
“Experts are telling us that Russian state actors broke into the DNC, stole these emails, and other experts are now saying that the Russians are releasing these emails for the purpose of actually helping Donald Trump,” he said. Mr Mook did not elaborate on the source of this information.
Last week, Mr Trump said that the US would not automatically come to the aid of a European NATO nation attacked by Russia if he becomes president.
Republicans have dismissed links between Moscow, the leak, and the US election as a conspiracy theory.
Donald Trump Jr told CNN, “I can’t think of bigger lies, but that exactly goes to show you what the DNC and what the Clinton camp will do. They will lie and do anything to win.”
US Secretary of State John Kerry raised the attack with his Russia’s foreign minister, Sergey Lavrov yesterday - but did not accuse the state of any wrongdoing. He said that he would not do so until the FBI concludes its investigation.