Marine Le Pen has accused France’s ruling class of being “intellectual terrorists” as she launches a final push in the second round of the country’s regional elections.

Speaking to a crowd of supporters in Paris, alongside her niece Marion, Ms Le Pen mocked France’s Socialists and the opposition conservative Republicans for ganging up on her party.

“Don’t be afraid of these totalitarians,” she said. “Don’t let yourselves be intimidated. Don’t give into this intellectual terrorism.”

The crowd cheered as she described France’s two traditional parties as a “lazy, treacherous mafia, an oligarchy” that kept the country’s out-of-touch elite in power.

The Socialists and Republicans are expected to join forces in Sunday’s second round in an attempt to keep Ms Le Pen’s National Front from power. One supporter, businessman Xavier Perthuis told The Times:

“We’re the first party of France now, but they’re going to make sure we don’t reap the benefit.”

The two traditional parties may nevertheless find the task a challenge. In last Sunday’s first round, Marion Maréchal-Le Pen scored 41 per cent of the vote in the region of Provence-Alps-Côte d’Azur, while her aunt received a similar result in Nord-Pas-de-Calais-Picardy.

Ms Le Pen also wished happy birthday to Marion, dressed in a black minidress, who turned 26 yesterday.

There is increasing evidence Europe’s establishment is now seriously worried about the popularity of the National Front. The Economist magazine today compared Ms Le Pen to Donald Trump and Hungarian Prime Minister Viktor Orbán, saying they all represent the “populist right”.

The magazine, which is widely regarded as a voice of global left-liberalism, even accuses them of leading a “xenophobic revival”. It warns, however, that establishment politicians should not underestimate them.

“Some mainstream politicians dismiss their arguments by labelling them fascist or extremist,” it says. “Yet such disdain risks suggesting that the elite is uninterested in the real grievances that populists play on.”