Former Ukip leader was invited to speak at event held by AfD party by the granddaughter of Hitler’s finance minister

Former Ukip leader Nigel Farage will appear at a rally held by Germany’s far-right party Alternative für Deutschland (AfD) inside a renaissance fortress in Berlin on Friday.

The South East England MEP will appear at the Spandau Citadel in the west of the German capital to talk about “developments in the European Union, Brexit, direct democracy” and “how to make the impossible possible”, according to AfD MEP Beatrix von Storch, who is hosting the event.

A granddaughter of Hitler’s finance minister, Lutz von Krosigk, von Storch is a leading member of the anti-immigrant party, which has realistic aspirations to enter Germany’s parliament for the first time in federal elections on 24 September.

Von Storch has been a member of Farage’s group in the European parliament since being expelled from the more mainstream European Conservatives and Reformists Group in April last year, following comments in which she called on European border guards to use firearms to deter illegal immigrants, including women and children. She later described the comments as a “tactical mistake”.

In her Facebook post, von Storch said that Farage had been so impressed with the AfD’s campaign that he had accepted “without hesitation” her invitation to appear at a campaign rally.

Protesters are planning to organise a counter-rally outside the Spandau Citadel while Farage is giving his speech, though by Thursday afternoon no official demonstration had yet been registered with Berlin police.

Farage has frequently criticised German dominance of decision-making in the European Union, while the AfD complains that the European Union dominates decision-making in Germany. In its manifesto, the party, which is currently polling between 8 and 11%, calls for a referendum on leaving the eurozone and for a British-style referendum on EU membership, unless the bloc returns to being “a federation of sovereign states”.

On the AfD’s social media channels a majority of users welcomed the announcement of Farage’s appearance, praising the former leader as a “straight-down-the-line” and “fiery” speaker. But some party members worried the event could backfire.

“Mr Farage was also the guy who bowed out after the referendum and left others to go through with Brexit,” said one user. “I will definitely vote for the AfD, because it’s the only alternative to our ‘government’. But is Nigel Farage really that helpful for our campaign given that the coverage is already so negative?”

In the run-up to Britain’s EU membership vote in June 2016, Farage said the then-US president, Barack Obama, had behaved “disgracefully” by warning on the economic consequences of a leave vote, and praised the Russian president, Vladimir Putin, who, he said, “maintained his silence throughout the whole campaign”.

Two months later Farage appeared at a rally with Donald Trump, where he stated: “I wouldn’t vote for Hillary Clinton if you paid me.”