BERLIN (Reuters) - The European Union’s fate rests on its ability to rise to the challenges of migration, a passionate Chancellor Angela Merkel told Germany’s parliament on Thursday ahead of a Brussels summit dominated by an issue that threatens her ruling coalition.

Speaking with uncharacteristic emotion and at times shouting down a rowdy Bundestag, the embattled German leader tried to win over critics from within her own conservative ranks.

Falling refugee numbers had ended the state of emergency that had caused her to throw open Germany’s doors to more than a million migrants in 2015, she said.

Merkel needs other European countries to come to her aid in facing down a rebellion by conservative coalition allies in Bavaria’s Christian Social Union, who demand that asylum seekers registered elsewhere in the EU be barred from entering Germany.

“Europe faces many challenges, but that of migration could become the make-or-break one for the EU,” Merkel told parliament. She said she would seek deals with “a coalition of the willing” if no deal with the bloc’s 28 members was possible.

Onward migration by refugees already in the EU must be better managed under such deals, she said.

“A person seeking protection in Europe can’t choose the country in which he makes the asylum claim,” he said. She added: “We cannot leave alone” countries, like Italy, that bear the brunt of the arrivals.

Europe’s migration crisis has tapered off, with the main route from Turkey to Greece used by more than a million asylum seekers in 2015 now largely shut. On the other main route, from North Africa to Italy, numbers have fallen this year to tens of thousands from hundreds of thousands.

But the political fallout is more acute than ever. Right-wing anti-immigrant parties won seats in Germany’s parliament for the first time since the 1940s in September, took power this month in Italy and are now fully entrenched in ex-Communist states of central Europe.

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“THE EUROPEANS WON’T BE BULLIED”

In Germany, the transformation in the political environment was plainly heard in Thursday’s parliament session, where the arrival of lawmakers from the far-right AfD has brought heckling to the chamber for the first time in the 13-year Merkel era.

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“Madame Chancellor, you are asking Europe to help you in a way that suits you. But the Europeans won’t be bullied,” said Alexander Gauland, co-leader of the AfD.

German President Frank-Walter Steinmeier urged the coalition parties to dial back the harsh rhetoric used in recent days, citing grave concerns voiced by European politicians that the dispute could undermine Germany as a stabilizing force.

“The wounds inflicted by public words will not heal easily,” he told the Frankfurter Allgemeine Zeitung newspaper in an interview to be published on Friday.

Merkel defended the defining move of her premiership against critics who accuse her of convulsing European politics with a unilateral decision to throw open Germany’s borders three years ago. “It was in no way unilateral,” she said, adding that she was responding to pleas from help from Hungary and Austria.

She said that reducing inward migration to the EU would require deals with African countries mirroring a refugee-harboring agreement signed with Turkey in 2016 that shut the route to Greece. That would require specific offers, such as study or work opportunities for their citizens, she said.

“Either we manage it, so others in Africa believe that we are guided by values and believe in multilateralism, not unilateralism, or nobody will believe any longer in the system of values that has made us strong,” she said.