BRUSSELS — European Union leaders are holding a summit in Brussels on Thursday without Hungarian politician Viktor Orbán for the first time in 16 years.

Prime ministers, chancellors and presidents have come and gone, but Orbán has been a stable fixture in Brussels’ halls of power, piloting Europe’s drift to the right and pioneering a brand of nationalist populism that has found growing success on the continent and is idolized by the Make America Great Again movement in the U.S.

Orbán, who is now Hungary’s leading opposition figure, had repeatedly clashed with the EU as he vilified its institutions and leaders and broke regulations as he hollowed out institutional checks and balances in Hungary.

Long a foil to EU ambitions in Ukraine and beyond, the former Hungarian prime minister, who lost a pivotal election in April, is now sitting on the sidelines for the first time in a generation — and watching as his successor Péter Magyar joins leaders including Spain’s Pedro Sanchez, France’s Emmanuel Macron and Germany’s Friedrich Merz as they advance policies likely at odds with Orbán’s vision.

As the EU summit opened to discuss ramping up support for Ukraine, among other things, Orbán was surrounded by his far-right allies from his new position outside the halls of power he once roamed.

Orbán was in the Belgian capital to take part in a Thursday summit of his Patriots for Europe party group, a collection of far-right parties from across the bloc that forms the third-largest caucus in the European Parliament.

Despite Orbán’s bruising election loss — welcomed with relief by many EU leaders and viewed by many observers as a rebuke of his combative approach to the EU and close ties to Russia — he’s remained steadfast in his belief that far-right parties in Europe are on the verge of a breakthrough.

Orbán told a news conference in Brussels on Wednesday that his election defeat had not interrupted “the rise of patriotic political organizations, communities, and parties across Europe.”

“No one election loss can stop this historical process,” he said. “Anti-migration and sovereigntist political forces in Europe will continue to grow stronger in the coming months and years.”

Orbán hopes the Patriots for Europe will be a vehicle for transforming the EU to his vision, for example, by decreasing the bloc’s purview in matters of rule of law and democracy, taking a zero-tolerance approach to immigration and steering toward deeper cooperation with Russia and China.

He had been the primary impediment to the EU’s efforts to draw Ukraine into the bloc. But Hungary’s new government, led by Magyar and his center-right Tisza party, has pledged more constructive cooperation with the EU.

Last week, Hungary lifted its veto on beginning Ukraine’s accession process after weeks of negotiations with Kyiv on restoring minority rights for ethnic Hungarians in western Ukraine.

“Hungary obviously had issues that they were able to resolve to allow this to happen this week,” said Thomas Byrne, Minister for European Affairs for Ireland, which will take the rotating EU presidency in July for six months. During that time, accession talks are slated to accelerate for Ukraine and Moldova, among others.

Europe’s far right has indeed scored some recent successes. France’s National Rally, led by Marine Le Pen, gained ground in municipal elections earlier this year, while Alternative for Germany (AfD) is performing increasingly well in polls. The populist leader of the Czech Republic, Orbán ally Andrej Babis, returned as prime minister last year and is now the only Patriots member who leads an EU-member nation.

They were able to deeply reform the EU’s migration policy, too, because of an alliance with the center-right European People’s Party. Human rights groups fiercely criticized the measures for increasing the bloc’s surveillance authorities, ramping up deportations of migrants, and the setting up of detention centers outside the EU dubbed “return hubs.” When the right-wing coalition won the vote to pass the migration reform on Wednesday, far-right and center-right lawmakers broke out in cheers inside the European Parliament chamber in Strasbourg, France.

“Send them back,” they chanted.

Still, fractures have emerged within Europe’s far right stemming from discomfort over the United States and Israel’s war in Iran as well as U.S. President Donald Trump’s threats to annex Greenland, a territory held by EU member Denmark.

And now that Orbán can no longer veto EU decisions — a tactic that increasingly defined his role at the bloc’s summits — Ukraine’s main obstacle to beginning the process of joining the EU has been taken off the table. ___

Spike reported from Budapest, Hungary. Associated Press writer Sylvain Plazy contributed to this report from Brussels.