The European Union approved a plan on Tuesday to share out 120,000 refugees across its 28 states, overriding vehement opposition from four ex-communist eastern nations.
The European Commission, the EU executive, had proposed the scheme with the backing of Germany and other big powers in order to tackle the continent's worst refugee crisis since World War Two.
But the rift it has caused between older and newer members was glaringly evident as the interior ministers of the Czech Republic, Slovakia, Romania and Hungary voted against the plan at a meeting in Brussels, with Finland abstaining.
"We would have preferred a consensus but we could not reach that, and it is not for want of trying," Luxembourg Interior Minister Jean Asselborn, whose country holds the rotating presidency of the EU, told a news conference.
Slovak Prime Minister Robert Fico said pushing through the quota system had "nonsensically" caused a deep rift over a highly sensitive issue and that, "as long as I am prime minister", Slovakia would not implement a quota.
And Czech Interior Minister Milan Chovanec tweeted: “We will soon realise that the emperor has no clothes. Common sense lost today.”
This year's influx of nearly half a million people fleeing war and poverty in the Middle East, Asia and Africa has already sparked unseemly disputes over border controls as well as bitter recriminations over how to share out responsibility.
Refugees and migrants arriving in Greece and Italy have been streaming north to reach more affluent nations such as Germany, prompting countries in central and eastern Europe alternately to try to block the flow or shunt it on to their neighbors.