The minister for industrial renewal, Arnaud Montebourg, laid into European Commission President Jose Manuel Barroso over his recent description of France's stance on a proposed EU-US free trade zone as "reactionary."
"Mr Barroso is the fuel of the Front National," Montebourg told France Inter radio on Sunday. "He is the fuel of (Italian protest party leader) Beppe Grillo."
Barroso has been in the firing line of French politicians of all shades since making dismissive remarks about France's insistence on excluding the film and television sectors from international trade liberalization under a policy known as the "cultural exception."
But Montebourg made the issue much broader by suggesting Barroso's comments were symptomatic of a deeper problem with the way power is wielded by the European Union's executive arm in Brussels.
"I think the main cause of the rise of the Front National is related to the way in which the EU today exerts considerable pressure on democratically elected governments," Montebourg said.
"You have the president of the European Commission who says 'all those who are anti-globalisation, they're reactionaries'. These are the same people who have today turned the European Union into an institution that is anti the people of Europe.
"In the end, the EU does not act, it is immobile, paralysed. It does not respond to any popular aspiration, on the industrial front, on the economic front or on the budgetary front.
"And in the end, that furthers the cause of all the pro-sovereignty, anti-European, parties in the EU."
Far-right beaten in by-election
Montebourg's critical comments came as the far-right National Front came second in a by-election for the seat vacated by disgraced former Budget Minister Jerome Cahuzac, in the south-western department of Villeneuve-sur-Lot.
The party's candidate, Etienne Bousquet-Cassagne, achieved 46 percent of the vote in Sunday's run-off against eventual winner, Jean-Louis Costes from the centre-right UMP party, after eliminating the Socialist candidate in last week's first round election.
Former Prime Minister Francois Fillon, one of the UMP's leaders, said the victory for his party's candidate would be welcomed by "all republicans".
But Fillon also acknowledged the recent advances made by the FN on the back of the Cahuzac scandal and France's economic problems were of concern for all mainstream parties.
"The elevated score of the Front National is a reflection of the despair felt by many French who have been let down by the false promises of the president of the republic," Fillon said. "It is also a warning for the opposition."