Artist and activist Ai Weiwei visited the Greek border camp of Idomeni on 9 March. Ai walked around the makeshift camp speaking with the migrants, seeing for himself the appalling conditions they have to brave as they wait to cross over to Macedonia and continue their trek northwards to wealthier European states.

Some 14,000 people are stranded there after new border restrictions were imposed along the Balkan migration route. Slovenia, Croatia and Serbia said on 8 March they would place new restrictions on the entry of migrants, and Macedonia responded by closing its border completely to illegal migrants. Ai, known for his criticism of his native China's human rights record, said he was witnessing a "huge, big violation of human rights" in the middle of Europe.

"What we have seen here is almost unbelievable. If you say this is in the middle of Europe, all the people stuck here and there's no hope for them even to be transferred to anywhere else you know. It's just in the rain, in the cold, and women, children, all the people waiting for some bread, or some dry clothes, and this is very sad situation and people have no hope because the door is closed, totally shut off," he said.

"I think this is huge, big violation of human rights, right in front of us. I don't know what is going to come out from this, but in Lesbos people still come in thousands every day, and here nobody tells them what to do, and they stay here, still having hope to go to Germany or some other location, but I think, as the sky is getting darker and I don't think there's much hope for them," he said.

People fleeing war and poverty in the Middle East and beyond have flooded into the EU since early 2015, most making the perilous sea crossing from Turkey to Greece, then heading north through the Balkans to Germany.