The leader of an ascendant right-wing party in Germany, Alternative for Germany, or AfD, says her party will push for a referendum seeking to extricate the country from the European Union if it comes to power.

In an interview with the Financial Times, Alice Weidel said Britain was “dead right” to leave the EU and that unless reforms are enacted curbing the power of what she called the “unelected European Commission” then her party would put the question of continued EU membership to German voters.

“If a reform isn’t possible, if we fail to rebuild the sovereignty of the EU member states, we should let the people decide, just as Britain did,” she said. “And we could have a referendum on ‘Dexit’ – a German exit from the EU.”

The AfD was set up in 2013 by conservative economists annoyed at the EU’s bailouts following the financial crisis of 2008. The party is leading the polls in five former East German states ahead of this fall’s local elections, and is polling at around 23 percent nationally — behind the more moderate Christian Democratic Union but ahead of all three parties in Chancellor Olaf Scholz’s governing coalition.

The party’s surge comes despite calls for it to be banned following reports that some of its leaders attended a meeting of far-right groups at Potsdam in November during which attendees called for the expulsion of millions of immigrants from the country. Ms. Weidel, who has led the party since 2022, did not attend the meeting and fired an aide who did.

Tens of thousands of Germans took to the streets of major cities over the weekend to protest the surging AfD. Protesters carrying signs reading “Never Again is Now,” “Against Hate” and “Defend Democracy” filled the streets of Hamburg, Stuttgart, Nuremberg, Frankfurt and other cities.

“From Cologne to Dresden, from Tuebingen to Kiel, hundreds of thousands are taking to the streets in Germany in the coming days,” Mr. Scholz said in a weekly video statement over the weekend, adding that the protesters’ efforts are an important symbol “for our democracy and against right-wing extremism.”