(AFP) – EU interior ministers were set to meet in Brussels Thursday to discuss the migrant crisis after western Balkan nations slammed shut their borders, exacerbating a dire humanitarian situation on the Macedonian frontier.

The scheduled two-day meeting will tackle various areas including a proposed deal with Turkey and the restoration of the visa-free Schengen zone, along with plans for a European border and coastguard system seen as a key step for securing the bloc’s frontiers.

The talks come after Slovenia and Croatia, two of the countries along the Balkan route used by hundreds of thousands of people in recent months, barred entry to transiting migrants from midnight Wednesday and Serbia indicated it would follow suit.

EU member Slovenia said it would make exceptions only for migrants wishing to claim asylum in the country or for those seeking entry “on humanitarian grounds and in accordance with the rules of the Schengen zone”.

Prime Minister Miro Cerar said the move meant that “the (Balkan) route for illegal migrations no longer exists”, while EU President Donald Tusk said on Twitter, “Irregular flows of migrants along Western Balkans route have come to an end”.

“Not a question of unilateral actions but common EU28 decision… I thank Western Balkan countries for implementing part of EU’s comprehensive strategy to deal with migration crisis,” Tusk added.

As the 28-nation EU battles the worst migration crisis since World War II, the fresh measures ramped up the pressure on the bloc to seal a proposed deal with Turkey to ease the chaos.

– A demand too far? –

A controversial deal discussed with Turkey at an EU summit on Monday and due to be finalised on March 17-18 would see the country take back all illegal migrants landing in Greece.

Ankara proposed an arrangement under which the EU would resettle one Syrian refugee from camps in Turkey in exchange for every Syrian that Turkey takes from Greece, in a bid to reduce the incentive for people to board boats for Europe.

In return though, Turkey wants six billion euros ($6.6 billion) in aid, visa-free access to Europe’s passport-free Schengen zone and a speeding up of Ankara’s efforts to join the EU — demands that go too far for some.

The country currently hosts 2.7 million refugees from the five-year-old Syrian civil war and is the main springboard for migrants heading to the EU.

Migrants wait for food at the Greek-Macedonian border near the Greek village of Idomeni on March 9, 2016, where thousands of refugees and migrants are trapped by the Balkan border blockade. (Getty)

– Hoping for a ‘miracle’ –

Authorities in Greece, the main entry point into the EU across the sea from Turkey, said Wednesday that nearly 36,000 migrants were now stranded there. Police said a further 4,000 were unaccounted for.

The UN refugee agency estimated Wednesday there were also as many as 2,000 migrants stuck in Serbia.

There are fears that some will turn to people-smugglers and try their luck getting into Albania, and from there to Italy, or into Bulgaria.

Meanwhile, more than 14,000 mainly Syrian and Iraqi refugees have camped out on the Greece-Macedonia border crossing — many of them for weeks — at a squalid camp.

Macedonia has not let anyone enter since Monday.

“We are hoping a miracle will happen,” said Ola, a 15-year-old from war-scarred Aleppo who has lived in a tent at Idomeni with her mother and two younger brothers for two weeks.

“We thought Germany wanted us. That’s why we took the boat and came here.”

Greek officials on Wednesday were trying to coax refugees to leave Idomeni for migrant centres elsewhere in the country. Many are reluctant to do so, however, fearing this would mean the end of their journey north.

More than a million people have crossed the Aegean Sea into Greece since the start of 2015, many from Syria, Afghanistan and Iraq and most aiming to reach wealthy Germany, Austria and Scandinavia.

This has caused deep divisions among EU members about how to deal with the crisis and put German Chancellor Angela Merkel under severe pressure domestically for her open-door asylum policy.

Speaking during a visit to Washington on Wednesday, Danish Foreign Minister Kristian Jensen said Merkel had underestimated how many people would arrive after “sending out invitations to refugees around the world”.