BRUSSELS — International aid groups on Tuesday slammed the European Union’s migrant deal with Turkey, as new figures showed that the number of people seeking asylum in Europe dropped by almost half last year compared with 2016.

The deal aimed to halt the flow of hundreds of thousands of people from Turkey — most of them fleeing Syria — to Greece in search of better lives in European countries. The number of people arriving on Greek islands dropped dramatically after the agreement. While EU leaders see the deal as a success, Amnesty International and Human Rights Watch say it leaves people trapped in hopeless situations.

‘‘The [EU-Turkey] deal is a glaring example of Europe’s failure to design and implement a unified refugee and migration policy which would respect the human rights of those crossing its borders seeking asylum,’’ said Jenny Kavounidi, board member of the SolidarityNow aid group.

ASSOCIATED PRESS