ATHENS, Greece, Feb 25, 2016 – Border closures in the Balkans may create an enormous and potentially critical refugee bottleneck in Greece, UN High Commissioner for Refugees Filippo Grandi has warned.

Grandi spent most of Wednesday (February 24) in Athens. meeting the Greek prime minister Alexis Tsipras and several of his ministers.

The potential bottleneck, Grandi said, was a major topic of discussion. The UN High Commissioner for Reguees once again criticized the border closures and the inability of European countries to face the refugee crisis with generosity and unity.

But he also said UNHCR and the Greek authorities must start planning for a situation where more than a few thousand people are stuck in Greece.

"I hope that there will not be a huge refugee population," Grandi said. "But that part can be managed, working together with the government in a timely way, in a rapid way. And we are ready for that. That was my message to the Prime Minister and to his ministers.

"But really we need to work on alternatives to that, we need to work on the restrictions, we need to work on relocation, we need to work especially on massive resettlement from Middle Eastern countries."

He said he would go to Brussels to address the EU's Justice and Home Affairs Council on Thursday (February 25) to bring the message that Greece, which is facing deep economic difficulties, will need considerable added aid, along with urgent implementation of the relocation scheme, to deal with the refugee bottleneck.

As he spoke, the evidence of the bottleneck was in the streets.

On Victoria Square in downtown Athens hundreds of people, many of them Afghan refugees, wandered about or sat on UNHCR blankets. Several of these people had traveled to the northern border with the Former Yugoslav Republic of Macedonia and been sent back by police.

Sayed was one of them. He, his wife and three young children had got to Greece last week and gone to the northern border. They and other Afghans were herded into a makeshift camp and held. Only Syrians and Iraqis with passports were allowed through.

Sayed, who is 30, helped draw up a petition of protest. It was refused and the Afghans were bussed back to Athens and left on the square at midnight. He and other men stood guard through the night to protect their families.

"We took our lives in our hands," he said. "We demand not to go back (to Afghanistan) because we are in danger there. Please open the borders for us, so we can move forward. We came here to save our lives."

The scope of the potential crisis was also evident in Elliniko, an abandoned stadium built for the 2004 Olympics. Hundreds of Afghans who had just arrived by ferry from the Greek islands were lining up to be admitted. Many knew the northern border was closed to them but none knew what they could do.

Upstairs, in a corner, Massoume cried. She is a widow from Afghanistan who managed to get to Greece with her two sons who are 13 and 20. The older son needs medical attention. She had planned to join her married daughter in Germany. Now she cannot.

"I am so alone here, I feel I am in a desperate situation," she said. "I tremble day and night. If the border doesn't open I don't know what will happen to me and my children."

Those are individual consequences of closed borders. Grandi warned of broader consequences, of Europe backtracking, losing its vision, values and lessening its influence in the world.

"The response," he said, "must be cooperation, not closures."

By Don Murray, Athens