LUXEMBOURG--Germany warned on Tuesday of a repeat of the chaotic influx of migrants that caught the European Union unprepared in 2015, as Greece and Cyprus sounded the alarm over a resurgence of arrivals from neighbouring Turkey.

  EU ministers met to discuss migration as Greece has again become the main gateway to Europe for people fleeing wars and poverty in the Middle East, Asia and Africa, with U.N. data showing nearly 45,600 arrivals by sea so far this year. "If we leave all the countries on the EU's external border (to fend for themselves), there will never be a common European asylum policy," German Interior Minister Horst Seehofer said.
  "And if there is no common European asylum policy, there is a danger that uncontrolled immigration will once again take place, throughout Europe. We have seen this before and I do not want it to happen again," he told reporters in Luxembourg.
  The bloc is wary of any recurrence of the 2015 crisis that sowed bitter divisions among EU states, strained social and security services and fuelled support for populist, anti-immigration, eurosceptic and far-right parties. Greece saw the highest monthly arrival numbers in August since the 2016 EU-Turkey deal that greatly reduced sea crossings there, according to a document - seen by Reuters - prepared by Finland, which currently holds the bloc's rotating presidency.
  Turkey has long complained that the EU support promised in exchange for keeping a lid on migration to Europe is inadequate given that it now hosts around 3.5 million Syrian refugees. The pressure on overcrowded migrant camps on Greece's Aegean islands is rising anew. Charity group Oxfam said over 13,000 men, women and children were now crammed into the Moria camp on Lesbos that was designed to accommodate 3,100 people.
  "The situation of children in the Moria camp is particularly worrying," Oxfam said in a statement, stressing that many of those under-age were on their own.
  Though the deal with Turkey helped contain the 2015 crisis, rights groups condemned it for undercutting international humanitarian law on providing safe haven for refugees, and aggravating the suffering of those already in distress. In return for Turkish help, the EU pledged 6 billion euros on refugee projects in Turkey. The EU says the money has since been delivered, but Ankara disputes this and has asked for more.
  "The situation in the Eastern Mediterranean is worrying," the bloc's top migration official, Dmitris Avramopoulos, said after Tuesday's meeting.