An aide to French presidential candidate Emmanuel Macron on Tuesday accused Russia of trying to derail his campaign by spreading false rumours, echoing charges of Russian meddling in the USA election.
Le Pen, the National Front party leader, said Thursday in an interview with France 2 TV that, if elected, French citizens would not be allowed to hold additional citizenship in non-European countries.
Macron's campaign manager Richard Ferrand had accused Russian Federation of committing "hundreds, if not thousands" of cyberattacks on his party's website since Macron announced his candidacy in November past year.
"The pundits are relying on history - in 2002, Jean-Marie Le Pen (Marine's father) went through to the second round but was defeated by Jacques Chirac, with the support of his opponents who could not bring themselves to vote for the controversial National Front candidate", he said.
The report appeared to play a part in Macron being forced on February 7 to kill rumors of an extra-marital gay relationship.
A top aide for the election frontrunner - and rival to Marine Le Pen - says Mr Macron has been the target of false reports spread by state-controlled media, including Russia Today and Sputnik.
Macron's strong pro-Europe stance was not to Russia's liking however, he said.
Russia Today, which is also funded by the government, denied the claims.
He has seen his poll lead evaporate following French press allegations that his wife had been paid for being his parliamentary assistant without doing any real work.
"It seems that it has become acceptable to level such serious charges at Russia Today without presenting any evidence to substantiate them, as well as to apply this "fake news" label to any reporting that one might simply find unfavorable", the news channel said in an emailed statement.
"That there is a hysterical anti-(President Vladimir) Putin campaign in certain countries overseas is an obvious fact".
An official French source said, however, that the question of cyber threats were being taken seriously and would be the focus of a defence council meeting of national security chiefs under President Francois Hollande.
"If these attacks succeeded, the campaign of En Marche would become extremely hard, if not impossible", Ferrand said in Le Monde online.