Updated

German Chancellor Angela Merkel on Friday robustly defended the European Union's deal to send back migrants to Turkey as polls pointed to deep skepticism at home about the accord, which human rights groups have criticized.

Merkel insists that the deal with Turkey, which hosts some 2.7 million Syrians, is the key to reducing the flow of migrants to Europe. The first migrants were sent back from Greece Monday.

The accord also calls for the EU to take in some Syrians directly from Turkey, funds for Ankara, visa-free travel for Turks and accelerated EU membership talks.

Merkel, a longtime opponent of full Turkish EU membership, said it is "right to try to cement its links to the European Union, without immediately having full membership in front of us" and to discuss visa freedom.

As for the deportations, Merkel said she is "firmly convinced that making clear we are pitting ourselves against illegal migration is right." She said Europe can't stand by and watch people smugglers taking control.

New polls for ARD and ZDF television indicated that Germans have little faith in the deal. ZDF found that only 38 percent of 1,261 people polled by phone this week believe the accord will result in many fewer migrants coming to Europe this year.

ARD's poll of 1,005 people, also conducted this week, showed 40 percent believe the number coming to Germany will drop. It also found that only 17 percent consider Turkey a trustworthy partner and 27 percent believe Turkey should eventually be admitted to the EU. It said 56 percent of respondents consider the deal bad, while ZDF found that 69 percent opposed it.

Both polls suggested that Merkel's popularity, which picked up after dropping at the height of the migrant influx, has stabilized. They gave margins of error of plus or minus around 3 percentage points.

Interior Minister Thomas de Maiziere said the deal with Turkey started well, but conceded that a significant drop in arrivals is due largely to other European countries' closure of the Balkan migrant route. Germany registered 173,707 new arrivals in the first quarter, only 20,608 of them in March, after seeing over a million last year.