Four people were rescued by the Turkish coast guard after the boat destined for Greece and carrying mostly Iraqi migrants sank off the Turkish holiday resort town of Kusadasi, the state-run Anadolu news agency reported.

Initial testimony of the migrants suggested there were no others missing, according to the news agency.

Only one migrant was a Syrian national and the remaining were Iraqis, it added. The nine dead all Iraqi nationals.

Turkey has been one of the main routes for migrants and refugees fleeing Syria and other trouble spots like Afghanistan and Iraq but numbers have fallen since the peak of 2015.

More than a million people, many fleeing the war in Syria, crossed to European Union member Greece from Turkey in 2015 after the onset of the bloc's worst migration crisis since World War II.

Turkey struck a deal with the EU in 2016 in an effort to stem the flow of migrants, agreeing to take back migrants landing on Greek islands in exchange for incentives including financial aid.