Greece and Turkey reached an agreement where Turkey accepted migrant returns from the mainland in order to reduce critical overcrowding in its refugee camps, a report said on Saturday.
According to sources, the agreement came during a strained two-day state visit by Turkish President Recep Tayyip Erdogan this week, during which he addressed revising borders and complaints about Greece's treatment of its Muslim minority.
On Friday, a Greek government source said Athens and Ankara had agreed "new measures of cooperation towards decongesting the islands, under the terms of the EU-Turkey pact."
The EU-Turkey pact was designed to encourage Ankara to stem refugee flows. Under that controversial deal, Ankara pledged to take back illegal migrants landing in the Greek islands in exchange for financial aid, eased EU visa rules for Turkish citizens, and limited direct resettlement of Syrian refugees living in Turkey.
The pact sharply reduced the number of migrants trying to cross the Aegean Sea to reach Greek islands, although Ankara has repeatedly threatened to walk away from the deal, including over the failure to fulfil the pledge on visa-free travel.
Greece said it found the pace of migrant returns to Turkey fell dramatically after a state crackdown on civil servants that followed an attempted coup against Erdogan in 2016.
Athens has until now been wary of moving large numbers of asylum seekers to the mainland, warning that doing so goes against the EU-Turkey pact.
On the islands of Lesbos, Chios, Samos, Kos and Leros where there are over 15,000 refugees and migrants, camps are filled to triple their capacity, forcing many to sleep in tents. Aid groups have warned that transferring refugees to heated accommodation before temperatures drop is a matter of life and death.