The European Commission launched a legal case on against Poland, Hungary and the Czech Republic for refusing to take in asylum seekers, ratcheting up a bitter feud within the 28-nation bloc about how to deal with migration.

The eurosceptic, nationalist-minded governments in Poland and Hungary have refused to take in anyone under a plan agreed by a majority of EU leaders in 2015 to relocate migrants from frontline states Italy and Greece to help ease their burden.

The Czech Republic, another ex-communist central European state, initially accepted 12 people but has since said it would not welcome more.

“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 on Tuesday, June, 13.

Avramopoulos said the Commission was therefore launching  infringement procedures against the three, a way for the executive arm to take to task countries that fail to meet their obligations. It opens the way for months, even years, of legal wrangling before a top EU court could potentially impose fines.