"Greece and Cyprus expressed concern with Turkish demand to open new chapters of the negotiation dossier on the country's accession to the EU," the source said.
On Monday, the Turkey-EU summit on migration took place in Brussels. The summit focused on stemming migration flows into the European Union. During the event, the sides discussed cooperation on migration, focusing on a speedy implementation of the EU-Turkey action plan approved in fall 2015.
Turkey pledged to take back all illegal migrants that had arrived to the European Union and send in their place legal Syrian refugees to the bloc on one-for-one basis in exchange for the acceleration of visa liberalization negotiations and EU accession talks.
Reaching agreement on the reunification of Cyprus, separated into a Greek south and Turkish north, is one of the conditions to accelerate the talks.