Ten people drowned while 43 others were rescued after a boat carrying migrants to Greece sank off Turkey's western coast, Turkish news agency Dogan reported on Saturday.

More than one million refugees and migrants arrived by land and sea in the European Union last year and some 3,600 died or went missing.

The Turkish coast guard was continuing search and rescue efforts where the boat sank off the coast of Ayvacik, a town across from the Greek island of Lesvos. It was not immediately clear how many migrants had been on board.

Five of those killed were children, the Dogan news agency said, and rescued migrants were hospitalised with hypothermia symptoms. It said the migrants were of Syrian, Afghan and Myanmar origin.

Around 500,000 refugees from the five-year-old war in Syria traveled through Turkey and then risked their lives at sea to reach Greek islands in 2015. Despite the winter conditions and rough seas, the exodus has continued, albeit at a slower pace.

Turkey is the first stop on Syrian migrants' journey to the European Union.

Turkey struck a deal with the EU in November pledging to help stem the flow of migrants to Europe in return for 3 billion euros ($3.3 billion) in financial aid for the 2.5 million Syrian refugees it is hosting, as well as renewed talks on joining the 28-nation bloc.