(Bloomberg) -- European leaders gather in Brussels on Sunday for an informal meeting aimed at paving the way to a deal on the management of migration, amid an escalating crisis that threatens to unravel the bloc’s passport-free travel area and dissolve Germany’s governing coalition.

Participating leaders arrive with different priorities: frontier countries including Italy seek more assistance from their peers with border protection and a more equitable allocation of refugees between the bloc’s member states. Northern countries, including Germany, want to limit “secondary movements” of protection-seekers from the south, where they initially apply for asylum, to the more affluent states of the European core.

With the bloc’s 28 nations at loggerheads over the overhaul of rules that assign responsibility for asylum-seekers to the countries of first arrival, but are not in practice enforced, the prospects for an EU-wide immigration agreement are slim, officials familiar with the discussions said. Germany will instead seek a patchwork of bilateral deals with frontier states, which would limit secondary movements in return for financial support and yet unspecified other concessions.

Even as the pace of arrivals has dropped sharply compared with previous years, a hardening rhetoric from Italy’s populist coalition and right-wing governments including Austria’s has soured relations among the bloc’s members. German Chancellor Angela Merkel is facing an ultimatum from her Bavarian allies to either strike a deal for limiting the influx of asylum-seekers by the end of this month or face a mutiny that could trigger snap elections.

“We must keep our calm and not yield to the extremes,” French President Emmanuel Macron said on Saturday. “National solutions can flatter some egos, but they’ll bring less-than-desirable results,” Macron said, clearly referring to Italian Interior Minister Matteo Salvini, who in recent weeks has played brinkmanship with other EU countries by refusing to accept humanitarian ships carrying migrants to Italian ports

EU government officials in Brussels said that if Merkel gives in to the demands of Bavaria’s Christian Social Union party to turn away refugees already registered in other EU countries at the border, then the entire Schengen Area of paperwork-free travel -- one of the bloc’s landmark achievements -- would be at risk of collapse.

Adding to her woes, Italy has said it won’t agree on a deal to limit flows towards Germany unless there’s an agreement to spread the burden of migration. But the so-called Visegrad countries of Czech Republic, Hungary, Poland and Slovakia, as well Austria, won’t sign off to any revamp of common rules that would force them to receive refugees from frontier countries.

In a sign of a widening rift, the four Visegrad leaders won’t join Sunday’s informal meeting, which is convened by the president of the bloc’s executive arm Jean-Claude Juncker. As of Saturday, only 16 nations had confirmed participation, while EU Council President Donald Tusk, who normally presides over gatherings of leaders, has refused to attend.

A formal EU summit is scheduled for June 28, in which migration will be among the key topics.

To contact the reporters on this story: Nikos Chrysoloras in Brussels at nchrysoloras@bloomberg.net;Gregory Viscusi in Paris at gviscusi@bloomberg.net

To contact the editors responsible for this story: Vidya Root at vroot@bloomberg.net, Steve Geimann

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