European Parliament lawmakers accused the EU Wednesday of giving Turkish President Recep Tayyip Erdogan the "keys to the gates of Europe" through a migration crisis deal with Ankara.

At a summit on Monday European Union leaders agreed to work for an agreement with Turkey that would include a 'one-for-one' swap of Syrian refugees and a doubling of aid for Ankara to six billion euros.

EU and Turkish leaders on Tuesday sought to turn into a lasting accord a plan on easing Europe's migrant crisis hailed as a game-changer by Ankara and Brussels but swiftly criticized by the U.N.'s refugee chief.

The day after agreeing the tentative plan following late night talks in Brussels, Turkish Prime Minister Ahmet Davutoglu was to discuss how it could work in a crucial meeting with his Greek counterpart Alexis Tsipras.

Turkish President Recep Tayyip Erdogan on Monday criticized the European Union for a four-month delay in disbursing a promised 3 billion euro fund for refugees agreed under a November deal.

"It's been four months. They are yet to deliver," Erdogan said in a speech in Ankara, as Prime Minister Ahmet Davutoglu held summit talks on the migrant crisis with EU leaders.

Turkish authorities have detained a Turkish boat owner and a suspected people smuggler over the latest sinking of a vessel carrying migrants in the Aegean Sea that left at least 25 dead, reports said on Monday.

The migrants, who included 10 children, died on Sunday when the boat carrying them on a bid to reach EU member Greece from Turkey sank in the Aegean in the latest deadly disaster on the route.

A leading Turkish newspaper which had staunchly opposed President Recep Tayyip Erdogan printed on Sunday its first new edition since its seizure by authorities, strongly supporting the government line.

Turkish police on Friday raided the Istanbul premises of the Zaman newspaper using tear gas and water cannon to enter the building in order to impose a court order placing the media business under administration.

European leaders will push Turkey at a summit on Monday to agree to "large-scale" deportations of economic migrants from Greece, as EU chief Donald Tusk says he sees the first hints of a resolution to the migrant crisis.

With a fresh surge expected in the warmer spring weather, the European Union's 28 leaders are pinning much of their hopes for reducing the chaos on new commitments from Turkish Prime Minister Ahmet Davutoglu.

An Istanbul court on Friday ordered into administration a Turkish daily newspaper that is sharply critical of President Recep Tayyip Erdogan, adding to growing alarm over freedom of expression in the country.

The Zaman newspaper, closely linked to Erdogan's arch-foe the U.S.-based preacher Fethullah Gulen, was ordered into administration by the court on the request of Istanbul prosecutors, the state-run Anatolia news agency said.

Turkish President Recep Tayyip Erdogan said Wednesday he was ready to help combat terrorism in Nigeria, where Boko Haram fighters have killed thousands of people in a bloody campaign for a hardline Islamic state.

He also signed a memorandum on trade and economic cooperation, which Nigerian President Muhammadu Buhari said was "just the beginning of what we have in the pipeline."

Turkey on Wednesday said it had proposed signing agreements with 14 countries on the return of migrants from EU member states.

Ankara had "offered to conclude readmission deals with 14 countries", foreign ministry spokesman Tanju Bilgic said at a weekly news conference without naming the countries.

Turkey on Wednesday denied claims that it was blocking NATO vessels deployed in the Aegean Sea from launching a mission to help stop the flow of migrants from Turkish shores to EU territory.

"Turkey has been the mastermind" of the proposed mission -- details of which have been held up by discord between Turkey and Greece -- foreign ministry spokesman Tanju Bilgic told a weekly press briefing in Ankara.