The European Commission has launched legal proceedings against three European Union member states who refused to take in refugees.
Poland, Hungary and the Czech Republic have been accused of not fulfilling their obligations outlined in a 2015 plan to relocate migrants from Italy and Greece, to help ease their burden.
"I regret to see that, despite our repeated calls to pledge to relocate, the Czech Republic, Hungary, and Poland have not yet taken the necessary action," the EU's migration commissioner, Dimitris Avramopoulos, told a news conference.
The Commission is now launching infringement procedures against the three nations, which would allow the top EU court to potentially impose fines. However, the legal battle could take months, even years, to conclude.
The Polish and Hungarian governments refused to take anyone in, while the Czech Republic initially accepted 12 people but has since said it would not welcome more.
Poland's Deputy Foreign Minister Konrad Szymanski told state TV that the action "unnecessarily heats up political tensions, of which there are already too many in the European Union".
He added: "If necessary, Poland is ready to defend its legal arguments in court."
In a separate legal battle on the matter, Hungary and Slovakia have challenged the agreement altogether in a top EU court and there will be an indication of the ruling due next month.
