Greek President Prokopis Pavlopoulos said Turkey was not doing enough to reduce the number of migrants arriving in Europe and accused Turkish port officials of helping people smugglers.
Turkey reached a deal with EU officials late last year to keep more refugees inside its borders and stop them traveling on. Thousands fleeing civil war in Syria have made the perilous journey from Turkey, across the Aegean Sea to Ankara's long-term regional rival Greece, many of them dying on the way.
"I greatly fear that Turkish people smugglers are getting support from the authorities," Pavlopoulos said in an interview with the Sueddeutsche Zeitung published on Monday.
"In particular, the port authorities act as if they don't notice anything. There are cases in which smugglers have supposedly been helped. We have evidence for this," he said.
Turkish officials were not immediately available to comment. Turkey says it is doing what it can to contain the movement of migrants and curb criminal smuggling gangs while accommodating more than 2 million Syrian refugees.
Pavlopoulos said Greece was still prepared to contribute towards the 3 billion euros ($3.27 billion) pledged by the EU to Turkey to help care for Syrian refugees as long as Ankara fulfilled its obligations.
"Up to now Turkey has not delivered," Pavlopoulos, who is due to meet with German Chancellor Angela Merkel later on Monday, told the paper.
The European Commission said earlier this month it was far from satisfied with Turkey's containment of migrants as the number of new arrivals to Europe remained far too high. [Reuters]