German Chancellor Angela Merkel speaks with Minister of the Chancellery Peter Altmeier | Sean Gallup/Getty Images ‘No reason for Plan B’ on migration deal: Merkel adviser Peter Altmaier dismisses Greek concerns that EU-Turkey deal is in peril.

The migration deal between the EU and Turkey is working so "there is no reason for a Plan B," according to a senior adviser to German Chancellor Angela Merkel.

Asked if he was worried about the future of the deal, Peter Altmaier, the head of the German Chancellory, told the Berliner Zeitung on Friday he was convinced "the agreement will last." He said the arrangement was in the interests of Germany and of Europe "but also in the interest of Turkey, which has taken in more refugees than any other European country."

Altmaier's remarks come after the Greek migration minister, Ioannis Mouzalas, said on Wednesday the EU should prepare a backup plan in case Turkey pulls out of the deal to stem the flow of migrants into Europe.

“We are very worried ... We need a Plan B," said Mouzalas.

At the height of last year’s migration crisis, thousands of asylum seekers arrived on Greek islands each day, but arrivals have fallen sharply since Turkey agreed in March to take back migrants reaching Greece, while Syrians in Turkey are resettled across the EU. In exchange, Turkey was promised billions in aid, progress on its path toward EU membership, and visa liberalization for its citizens.

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