The French president, Emmanuel Macron, has described European nationalists as “hidden Brexiteers” selling the public the “same lies” as those who campaigned for Britain to leave the European Union.

In an interview with the Economist, Macron said the only way to stop the rise of nationalism was by “being bold enough not to think that their rise is inevitable”.

And he reiterated that he did not rule out sending French troops to Ukraine if Russia broke through frontlines and Kyiv requested soldiers.

Macron gave the interview after a speech last week in which he declared that Europe was “mortal … and could die” in part because of the existential threat posed by Russian aggression following Moscow’s invasion of Ukraine in February 2022.

He was speaking weeks before European elections in June in which the far-right Rassemblement National (RN) is expected to win with a crushing majority against Macron’s centrist Renaissance party. It is not alone: across the 27-member bloc, most polls predict the biggest gains for the far-right Identity and Democracy (ID) group in the European parliament, which includes Germany’s Alternative für Deutschland (AfD) and Italy’s Lega.

“What kills me, in France as in Europe, is the spirit of defeat. The spirit of defeat means two things: you get used to it and you stop fighting,” said Macron.

“The second is “what’s-the-pointism”, cowardice. People look at the polls, but polls don’t make politics. It’s your ability to get things done that does. And so everyone says that nationalism is on the rise. Obviously, that’s simpler. But nationalists are distorting the European debate.”

Pointing to the effect of Britain’s decision to leave the EU, he added: “Brexit has impoverished the United Kingdom. Brexit has done nothing to solve immigration in the UK. Well, despite that, some people think it doesn’t look so bad, but nobody dares to say that anything is wrong. And so nobody is taking responsibility for anything.”