In an interview with the German newspaper "Bild am Sonntag," Martin Schulz (pictured above, left) said the European Union "must not be silent on violations of fundamental rights in Turkey just because we are cooperating on the refugee question."

"On the contrary, we must denounce these violations and permanently stay in discussions with Turkey on freedom of expression and human rights issues," Schulz said.

Schulz's comments on Sunday came just days after Turkish President Recep Tayyip Erdogan (pictured above, right) called in the German ambassador over a satirical video that mocks the Turkish leader. It was aired earlier in March by German broadcaster NDR.

The president called for the song, "Erdowie, Erdowo, Erdogan" (a play on the Turkish leader's name and the title of a 1980s German hit song), to be pulled from air. The satirical song included lyrics such as "a journalist who writes something that doesn't suit Erdogan is in jail tomorrow."

"It is unacceptable that the president of another country demand that we restrict democratic rights in Germany because he feels he was caricatured," Schulz said, arguing that Erogan's reaction was a "step too far."

Optimistic outlook

Despite his criticism of Erdogan, Schulz also said in the interview that he was optimistic about the suceess of the EU's refugee deal with Turkey.

Under the controversial deal, the European Union will take in Syrians currently housed in Turkey and resettle them in EU countries on a one-to-one basis for Turkey's taking back rejected migrants from Greece. This is designed to eliminate incentives for migrants to come to Greece by boat.

"All EU countries have agreed to this scheme. Germany alone is ready to accept 40,000 refugees, France 30,000 and Portugal 10,000.

"And once we have managed to distribute a first group in the EU, I am confident that it will work from then onwards," Schulz said.

Easing pressure

The EU parliamentary president said that the refugee pressure in Europe would ease this year, compared to 2015, which saw the arrival of more than one million asylum seekers in Germany alone.

"The cease-fire in Syria has now held for more than two weeks already. This is a record," Schulz added.

"The 'Islamic State' terrorists are being driven back," he said, adding that new financial aid had also improved conditions in refugee camps in Jordan and Lebanon.