LIMASSOL, Cyprus (AP) — The rift over how to handle Europe's immigration crisis ripped wide open Friday. As nations along the Balkans migrant route took more unilateral actions to shut down their borders, diplomats from EU nations bordering the Mediterranean rallied around Greece, the epicenter of the crisis.

Cypriot Foreign Minister Ioannis Kasoulides — speaking on behalf of colleagues from France, Spain, Italy, Portugal, Malta and Greece — said decisions on how to deal with migrant influx that have already been made by the 28-nation bloc cannot be implemented selectively by some countries.

"This issue is testing our unity and ability to handle it," Kasoulides told a news conference after an EU Mediterranean Group meeting. "The EU Med Group are the front-line states and we all share the view that unilateral actions cannot be a solution to this crisis."

Kasoulides urged EU countries to enact all EU decisions on immigration so there "will be no unfairness to anybody."

Greek Foreign Minister Nikos Kotzias blasted some European nations for imposing border restrictions on arriving migrants, saying that police chiefs are not allowed to decide to overturn EU decisions.

He said Mediterranean colleagues were "unanimous" in their support for Greece's position on the refugee crisis and that there was "clear criticism to all those who are seeking individual solutions at the expense of other member states."

The Greek government is blaming Austria — a fellow member of Europe's passport-free Schengen Area — for the flare-up in the crisis. Austria has imposed strict restrictions last week, creating a domino effect as those controls were also implemented by Balkan countries further south along the Balkans migration route.

Greece recalled its ambassador to Austria on Thursday and rejected a request to visit Athens by Austrian Interior Minister Johanna Mikl-Leitner.

Thousands of migrants are pouring into Greece every day but now, if they are unable to move north due to borders closures, officials fear the country could turn into "a giant refugee camp."

In Munich, German Chancellor Angela Merkel echoed the Mediterranean EU ministers in calling for a unified European approach to tackle the migrant crisis. Merkel, who has said that those fleeing violence deserve protection, said she was encouraged by the recent deployment of NATO ships to the Aegean Sea alongside vessels from the European Union border agency Frontex.

"NATO has started to work in collaboration with the Turkish coast guard and Frontex. It is too early to see the effects of this measure. All 28 (EU) member states want to stop illegal immigration," she said.

But NATO Secretary-General Jens Stoltenberg said the ships would only be providing a support role.

"NATO ships will not do the job of national coastguards in the Aegean. Their mission is not to stop or turn back those trying to cross into Europe," he wrote.

Meanwhile, Greek government officials said Friday that arriving refugees and other migrants will be kept on Aegean Sea islands and on ferries used as floating shelters.

Ferry companies were instructed to limit the number of migrants traveling by ferry to the Greek mainland, where thousands have been sleeping outside in city parks and along the country's highways since Greece's existing migrant shelters are filled to capacity.

In Athens, migrants staged peaceful protests, briefly blocking traffic at the country's main port in nearby Piraeus.

"All the people around here are looking to get to Germany," Afghan migrant Muchtar Ahman said, speaking at a central Athens square where he was camped out with friends. "But ... (with) the Macedonian borders closed, we are really disappointed. We are hopeless. We are homeless."

Merchant Marine Minister Theodoros Dritsas said up to two-thirds of the migrants arriving on Lesbos and other Greek islands would be held there until Sunday.

"We need more time to prepare additional sites for temporary shelters," Dritsas said.

He said three chartered ferries — with a combined capacity of about 4,000 places — would be used on islands to provide temporary shelter over the next three days.

About 2,000 people — more than half from Syria and Iraq — are arriving daily from Turkey using dinghies and small boats, but the number of people crossing into neighboring Macedonia has dropped dramatically in the past week, and was down to just 150 on Thursday, according to Greek police figures.

By early afternoon Friday, not a single migrant had crossed into Macedonia, while 4,500 people waited nearby, according to Greek police.

In Serbia, police said they been formally notified by Croatia and Slovenia that only 580 people per day would be allowed to cross the border.

Athens says it is unable to stop migrants from crossing its sea borders without endangering their lives.

Thanassis Stavrakis and Raphael Kominis in Piraeus, Greece; Costas Kantouris in Thessaloniki, Greece; and Jovana Gec in Belgrade, Serbia, contributed to this report.

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