Hungarian Prime Minister Viktor Orban (left) and Luxembourg Foreign Minister Jean Asselborn (Thierry Charlier and John Thys/AFP/Getty Images)

Luxembourg's foreign minister issued a stern warning to Hungary's right-wing government Tuesday, arguing that its anti-refugee policies justified expulsion from the European Union.

Hungarian Prime Minister Viktor Orban's refusal to accept refugees — and instead construct border fortifications -- "massively violated" the principles of the European project, said Jean Asselborn, Luxembourg's top diplomat.

"We cannot accept that the basic values of the European Union are being so seriously breached,” Asselborn said, speaking to German newspaper Die Welt.

“Anyone who, like Hungary, builds fences against refugees from war or who violates press freedom and judicial independence should be excluded temporarily, or if necessary forever, from the E.U.,” he said.

The rhetorical broadside, the Financial Times noted, marks the "first time an E.U. foreign minister has called for another member state to be expelled from the bloc."

As WorldViews has discussed frequently over the past year, Hungary has been at the vanguard of Central and Eastern European states that have balked at proposed E.U. plans for the resettlement of 160,000 refugees, including many desperate families from war-stricken Syria, across the continent.

On Oct. 2, Hungarians will vote in a referendum on whether to accept the E.U.'s relocation plan. Orban's government is aggressively campaigning against it and recently distributed an 18-page pamphlet, funded with taxpayer money, demonizing refugees and migrants. "Forced settlement endangers our culture and tradition," it states.

Orban has framed his nation as a Christian bulwark against a supposed Islamic invasion. Despite the minuscule Muslim population in his country, he thinks that refugees from the Middle East pose a fundamental cultural threat.

Asselborn's Hungarian counterpart, Peter Szijjarto, hit back in an email to a Hungarian news agency, deeming the Luxembourg diplomat a "frivolous character," "an intellectual lightweight" who "lives a sermonizing, pompous and frustrated life … just a few kilometers from Brussels," according to the Financial Times.

Szijjarto went on to draw attention to Luxembourg's controversial tax deals with multinational companies before making a nationalist appeal.

“But we all know that simply means making Hungary bear the burden of others’ mistakes," he said. "The Hungarian government refuses — the Hungarian people will give their opinion on October 2.”

The tension between the two senior officials captures the fundamental conflict within the E.U. In numerous countries, populist nationalism — shaped by xenophobic politics as well as economic grievance with the continent's plutocrats and bureaucrats — is weakening support for the European project and the mandates of Brussels.

Leaders and policymakers in various Western European capitals recognize the importance of a unified, integrated Europe at a time when the weight of global political and economic power no longer rests with the continent. But public opinion has soured against such efforts.

"Instead, many Europeans are following populist banners back toward the nationalism and isolationism of the nineteenth and early twentieth centuries," wrote former German foreign minister Joschka Fischer in a column last month.

"This doesn’t bode well for Europe. In the twenty-first century, the turn away from cooperation and integration amounts to burying one’s head in the sand and hoping the dangers will pass," Fischer warns. "And, in the meantime, the resurgence of xenophobia and outright racism is shredding the social fabric that Europe will need to prevent threats to peace and order."

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