The National Front (FN), the French far-right political party, will look to dump the Euro and return France to using the Franc, if its candidate Marine Le Pen wins the country's presidential election in May, one of her top advisors has said.

The economic strategist for the FN, Bernard Monot, told the Sunday Times he believed the new Franc would fall by 20% against the Euro, adding that Le Pen would look to reinstate the old currency within the first six months of her presidency.

"We want to take back control of our national borders," Monot said. "Countries need frontiers to regulate capital, goods and people," he added.

With a hardline populist narrative, Le Pen is currently polling as the most popular candidate as she and her rivals head into the first round of the presidential elections in April.

The elections have already been dogged by scandal, with Francois Fillon, the republican establishment candidate accused of paying members hundreds of thousands of Euros for civil service work they never did.

Presidential candidate Francois Fillon as he addressed reporters in Paris on 6 February, 2017. Reuters

Le Pen, who has run on an anti-immigrant platform, has also pledged to remove France from the EU if she wins and will revoke dual citizenship for French nationals.

As Fillon's popularity has waned, polls suggest he may be eliminated in the first round of voting in April's election, sparking a likely run-off between centrist Emmanuel Macron and Le Pen.

Despite her robust support, Le Pen remains unlikely to win in the final run-off.

Under the system, the two candidates with the largest share of the votes face each other in the second round votes, guaranteeing the president a majority and a mandate to govern.

It is believed Le Pen, whose populist policies are deeply divisive, would unite all opposition against her in such a scenario.

Monot, a member of the European parliament, has said he has been in conversations with EU officials about France's leaving the Euro.

"They are all capable of understanding that if France leaves the eurozone and the European Union then there is no more euro and no more European Union," Monot said.