US firm says Russia behind Macron hack

"If indeed driven by Moscow, this leak appears to be a significant escalation over the previous Russian operations aimed at the US presidential election, expanding the approach and scope of effort from simple espionage efforts towards more direct attempts to sway the outcome," he said.

APT 28, which is also known as APT10, APT 29, Fancy Bear, and Pawn Storm has been said by US authorities to be a front for Russia’s GRU military intelligence service.

It was also said, in April, by the Tokyo-based firm Trend Micro, to have tried to hack the campaign team of Emmanuel Macron, the incoming French leader.

The similarity of what happened in France to events in the US election last year, where the GRU was said to have hacked emails from Hillary Clinton, the Democratic Party candidate, also drew fresh accusations.

Clinton’s former press secretary, Brian Fallon, said on Twitter over the weekend that: “[Russian leader] Putin is waging war against Western democracies”.

Clinton former campaign manager, Robby Mook, said: “For those who thought Russia was dialing back. Macron's French presidential campaign emails leaked online”.

The stolen Macron files purported to show financial irregularities.

They were posted online in the early hours of Saturday morning by accounts linked to right-wing US activists, then popularised by the WikiLeaks website, and later spread by social media users linked to Russian state media.

WikiLeaks drew accusations of being a Russian regime stooge after it published Clinton’s leaked emails last year.

It appeared to turn against Russia on Sunday by saying that a Russian firm called Evrika, which had links to Russia’s FSB intelligence service, had been implicated in data linked to the Macron hack.