Serial provocateur and former Breitbart editor Milo Yiannopoulos is due to open a conference next month organised by the Hungarian government that also features a prominent German right-wing activist.
Budapest describes the three-day event called "The Future of Europe" beginning January 23, as an "opportunity to analyse the full array of political and cultural processes".
The 33-year-old Briton will speak on "Challenges of the Western World", while Gotz Kubitschek, a figure linked to Germany's "neue-rechte" movement will also deliver a keynote speech.
Other scheduled speakers include French philosopher Pascal Bruckner, Hungarian Foreign Minister Peter Szijjarto and an MEP from Fidesz, Hungary's ruling rightwing party led by Prime Minister Viktor Orban.
Yiannopoulos casts himself as a gay crusader for free speech and against "political correctness" in all its forms -- and has revelled in provoking the outrage of America's liberal left, which accuses him of spreading hate.
But he lost a book deal and resigned from an editorial position at the right-wing news site Breitbart last February amid a storm triggered by a video leaked on Twitter in which he seemed to condone paedophilia.
The Budapest event comes shortly before a general election expected in April when the fiercely anti-immigration Orban, like Yiannopoulos a staunch fan of US President Donald Trump, is forecast to win a third consecutive term in office.
A pro-Orban news-site called Yiannopoulos "one of the architect's of Trump's success" and his upcoming visit a "historic moment".
"It will be a dream come true for many," said PestiSracok.hu.
In 2014 however, Hungary banned a conference of the US-based National Policy Institute led by a Yiannopoulos associate, the white supremacist leader of the so-called "alt-right" movement Richard Spencer.
That conference, also called "The Future of Europe", included on its speaker list Philippe Vardon, a close associate of French far-right leader Marine Le Pen, and Alexander Dugin, a Russian political scientist who promotes the so-called Eurasian empire.