Only 18 refugees and migrants have entered Greece by sea over the past 24 hours, a week after a European Union deal to deport new arrivals back to Turkey went into effect.

However, just over 53,000 remained stranded Monday in Greece, through which more than a million people from the Middle East and Africa have passed since the beginning of 2015, heading to more prosperous European countries.

Arrivals, mostly in frail smugglers' boats from Turkey, peaked above 200,000 in October. Following last month's EU-Turkey deal the numbers have dropped, with just 1,704 arrivals so far this month — about 189 daily.

About 11,000 migrants live in a tent city on the closed Macedonian border, hoping to continue north, despite repeated appeals from Greek authorities to relocate to organized shelters.