Macron's party raises alarm on Russian hackers

“We want a strong Europe. That’s why we’re suffering attacks on so many websites apparently by the Russian state,” he added.

He urged French voters to beware of “fake news from Russian media which have come to weigh on our democratic life”.

He also said En Marche! had “asked the highest authorities in France to make sure there’s no Russian interference in this campaign”.

Ferrand spoke after Russian state media last weekend began circulating rumours that Macron, a centre-left politician, had had a gay extramarital affair.

The Sputnik news website started the ball rolling on 4 February in an interview with Nicolas Dhuicq, a pro-Russian centre-right French MP who has visited Crimea and who said it rightly belongs to Russia, in which Dhuicq portrayed Macron as a puppet of US elites and claimed that revelations about his unconventional private life would soon come to light.

“There is a very wealthy gay lobby behind him. This says it all,” Dhuicq said.

Russia’s flagship TV news show, the News Of The Week, the following day also ran a report saying “Macron is married to his French teacher from school who is 24 years his senior, but there are still rumours about his non-traditional [sexual] orientation”.

Macron himself laughed off the unsubstantiated claims about his sexuality, saying that perhaps his “hologram” had had a gay affair, but they were spread and discussed on social media and could cause lingering harm to his public standing.

The sexual slur comes amid earlier unsubstantiated claims by Sputnik France that Macron was involved in "scandals" concerning party funding and that French media was biased toward him.

Wikileaks founder Julian Assange, whose website backed the pro-Russian Donald Trump in the US election by publishing Russian hacks of his opponent's emails, has also promised Russian state media to release compromising information on Macron in a sign that the smear campaign is far from over.

Ferrand’s warnings on Monday’s talkshow come amid wider concern over Russian interference in the French and upcoming German elections.

Russia has already been outed for funding the anti-EU and pro-Russian far-right candidate in France, Marine Le Pen, and has been accused of subsidising Germany’s anti-EU party, the AfD.

Spy chiefs in France, Germany, the UK and the US have all echoed Ferrand’s concerns in recent weeks.

The French satirical journal, Le Canard Enchaine, last week cited a source in the French intelligence service, the DGSE, as having said that Russia would release compromising material on Le Pen’s opponents and that Russian bots would spread pro-Le Pen messages on social media.

It also reported that the French national security council was holding meetings on the subject.

According to polls, Le Pen will get into the second round of French elections in May but is likely to be beaten by either Macron or by the centre-right candidate Francois Fillon.

Fillon also has Russia-friendly views and was favoured by the Kremlin, but his chances of securing victory have been harmed by financial irregularities surrounding his wife’s alleged fake job.

Meanwhile, Nato’s communications services have said that Russia’s broader disinformation campaign in Europe has mushroomed since its invasion of Crimea in 2014.

"Nato has been dealing with a significant increase in Russian propaganda and disinformation since Russia's illegal annexation of Crimea in 2014," its spokeswoman, Oana Lungescu, told Reuters and the BBC in separate interviews.

She cited as one example a report by the life.ru website which was based on a fabricated audio file purporting to be the Nato secretary general Jens Stoltenberg in conversation with Ukrainian leader Petro Poroshenko.