Greek authorities in coordination with Turkish and European authorities made final preparations on Saturday for the start of the return of refugees from the Greek Aegean Sea islands to Turkey on Monday, while NGOs were scheduling protests. Under March's European Union (EU)-Turkey agreement, from April 4 migrants who entered Greece via the Aegean after March 20 and were declared not eligible for asylum protection in Greece will be readmitted to Turkey, Xinhua reported. According to sources the process will start from the port of Mytilene on Lesvos island on Monday. Two Turkish vessels have been chartered by the European border control agency Frontex via Greek shipping companies to transfer the first batch of migrants from Lesvos to Turkey. The "Nazli Jale" will carry a total of 200 refugees escorted by 200 Frontex officers per day and "Lesvos" will transfer a total of 100 persons per day (50 refugees and 50 security officers). Under the deal which was ratified by Greece's parliament on Friday, Athens, Ankara and European partners will be cooperating in order to curb the massive refugee influx into Europe via the Aegean. More than a million people have landed on Greek shores since January 2015. Humanitarian organisations have expressed concern over the process and whether the refugees will receive full protection in Turkey under international law and according to sources are planning to hold protests at Mytilene port on Monday.