President Erdogan accused Greece of condemning refugees to death by skewering their boats, adding Turkey had "all the documents" to confirm his claims.
Turkey's President Recep Tayyip Erdogan has stated that blaming Turkey for the refugee crisis is a "real ingratitude''.
Erdogan's statements on Thursday come after a meeting with Hungarian Prime Minister Viktor Orban in Turkey's capital Ankara.
"It is Greece that is condemning refugees to death by skewering their boats," Erdogan said during a televised news conference alongside Orban.
He also added that Turkey had "all the documents" to prove his claims.
"I have no idea how Greece would handle it if Turkey opened the doors" to migrants attempting to reach Europe, as it briefly did during an escalation of the dispute early last year, Erdogan said.
Orban underlined the need for a defensive perimeter around Europe, noting that the continent was under migration pressures from the Mediterranean, Western Balkans, and Belarus.
He said that Europe was in need of allies, and if such a perimeter is not established, the continent would be in a "difficult situation."
"We should help our Turkish friends on migration. The EU should support Turkey as much as possible," Orban said.
Erdogan said that the two had discussed bilateral relations, international and regional issues, and economic and commercial ties during the meeting.
He noted that the current trade volume between the two countries was $3-4 billion, and they seek to raise this figure to $6 billion.
Tensions over refugee crisis
On Tuesday, Greek Prime Minister Kyriakos Mitsotakis said Greece intercepted boats that came from Turkey, denying claims of pushbacks by authorities.
"So rather to put the blame on Greece you should put it on those who have been instrumentalising migration systematically," Mitsotakis said.
Ankara and Athens are often at loggerheads over migration, with the NATO allies accusing each other of failing to honour a deal to curb the flow of migrants passing through Turkey to Europe.
Turkey signed a deal worth $7.2 billion (six billion euros) with the European Union in 2016 to stem the flow of migrants after more than a million people fled to Europe in 2015.
Turkey hosts 4 million refugees, more than any country in the world, amid signs that a new wave of Afghan refugees might head towards Turkey and the EU.