More than 500 migrants arrived overnight on the Greek island of Lesbos, authorities and NGOs said on Friday, as Greece complained that the number of new arrivals is surging.

Thirteen boats carrying 540 people, including 240 children, arrived late Thursday from nearby Turkey, Doctors Without Borders, or MSF, said.

They were taken to the island's already densely overcrowded Moria migrant camp, where "nearly 11,000 people are crowded together in a camp whose capacity is actually only for 3,000," MSF said.

According to a Greek diplomatic source, Foreign Minister Nikos Dendias summoned Turkey's ambassador in Athens to express "his great displeasure" at the recent increase in the number of arrivals from Turkey.

Dendias reminded the Turkish envoy of Ankara's obligations under a 2016 deal with the EU aimed at reducing the flow of asylum seekers to Europe, the source said.

Athens had also informed Brussels about the latest increase in numbers, it added. 

The Greek islands "have reached their limits," Alexandros Konstantinou, a lawyer for the NGO, Greek Council for Refugees, told AFP. 

According to the International Organisation for Migration, 3,250 arrivals were registered on the five islands of Lesbos, Chios, Samos, Leros and Kos during the first two weeks of August, compared with 5,520 in the whole of July and 2,079 in January. 

Greece's new conservative government under Kyriakos Mitsotakis has similarly said that the number of migrants arriving on its islands is higher than last year.