European Union ministers are meeting to try to resolve a dispute over how to relocate 120,000 asylum seekers who have recently arrived in Europe.
Some central European states have resisted calls for EU members to accept mandatory quotas.
Whatever is decided, the UN says the EU’s plans will not be enough.
The migrants are part of 500,000 to have arrived by sea this year so far. Germany says it expects at least 800,000 this year.
The arrival of hundreds of thousands of migrants has created deep EU divisions.
Home affairs ministers meeting in Brussels on Tuesday are hoping to reach agreement which would be ratified by EU leaders on Wednesday.
Hungary, Poland, Slovakia and the Czech Republic all oppose the idea of obligatory quotas, promoted by Germany, which has accepted large numbers of migrants.
German Chancellor Angela Merkel said two weeks ago that obligatory quotas were “a first step” towards a more permanent scheme to deal with the influx.
But mandatory quotas have now been dropped, diplomats say, and a voluntary relocation scheme is now on the table.
Refugees and migrants have been walking over the border from Hungary. The young men come first, waving and asking: “Is this Austria?”
There are cheers when they are told where they are.
The families follow, a father holding the hands of his two young children, a mother carrying her baby, then a man pushing a boy in a wheelchair.
Many are from Syria – others say they are from Afghanistan, Iraq and Pakistan. Some walk to the reception centre where the Red Cross has food and clothes for them. But others go straight to the queues for the buses which will carry them away from the border.
Some apply for asylum in Austria but most say they want to go on to Germany.