National Rally leader Jordan Bardella broke the uneasy calm in France's financial markets on Thursday with a vow to claw back billions of euros from the EU if his party forms the next government.

In an interview with the Financial Times, the 28-year-old Bardella vowed to use the “weight” of a potential National Rally election victory to cut France’s contributions to the EU budget by €2 billion.

“I want to get a rebate,” the FT quoted him as saying.

The yield on 10-year French government bonds, a rough market barometer of political risk, hit its highest in nearly three weeks after the publication of the comments on Thursday morning.

Financial markets were already nervous at the prospect of a sweeping victory for the National Rally, amid fears it would roll back many of French President Emmanuel Macron's deep spending cuts in defiance of EU fiscal rules. The president has been trying to defend France's market credibility, after persistent and wide budget deficits earned it a credit rating downgrade and a rebuke from the EU.

National Rally leaders have been trying to balance the demands of international markets against those of their base. After an initial shock, markets calmed down last week as Bardella and others insisted that his government would cooperate in a potential “cohabitation” scenario with Macron, and soft-pedalled on some of their more expensive spending plans.

However, the floating of a multibillion euro rebate shows that conflict with the EU is still in play — albeit not directly over the fiscal rules that are the markets' chief concern.

National Rally, the party of right-wing stalwart Marine Le Pen, is projected to win the first round of voting comfortably, scoring over 30 percent of the vote, according to POLITICO's Poll of Polls.

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