The French far-right on Saturday accused the left of seeking to "undermine civil peace" should Marine Le Pen win the presidential election next spring, underscoring the increasingly confrontational tone of the campaign.
With less than eight months to go before France's presidential election, far-right leader Le Pen, 58, remains the front-runner in the polls.
Analysts say that the appeal of political extremes is growing in France, and recent surveys show that hard-left presidential candidate Jean-Luc Melenchon, 75, may have the best chance of reaching the run-off against Le Pen.
Speaking at an agricultural fair in the northeastern town of Chalons-en-Champagne, Jordan Bardella, president of the National Rally (RN) party and Le Pen's prospective prime minister in the event of her victory, said he was concerned by calls from the left for "civil disobedience" if the RN comes to power.
Bardella, 30, said they amounted to "an admission of weakness from the left, which hates democracy and is calling into question the fundamental principles of the rule of law and the electoral process."
"The attitude of France Unbowed at the start of this campaign is deeply worrying," said Bardella.
"They are already seeking to undermine civil peace in our country."
Mathilde Panot, leader of the LFI parliamentary group in parliament's lower house, and Greens leader Marine Tondelier have recently said they would support "civil disobedience" in the event of an RN victory.
Some observers say the election campaign is increasingly at risk of becoming a contest dominated by populist anti-establishment forces, raising concern among investors about the prospect of a presidential runoff between the far right and the hard left.
Bardella said he was concerned about Melenchon's "true intentions."
During a first presidential debate on Thursday, Melenchon vowed to "disobey" European decisions that contradict the wishes of French voters and pressed ahead with his proposals to cancel a chunk of France's public debt.
"France Unbowed and Monsieur Melenchon do not want to win this presidential election," said Bardella.
"They do not want to protect institutions, they want to destroy them."
