Hungary, Poland, the Czech Republic and Slovakia are ready to veto any Brexit deal that would limit their citizens' rights to work in Britain, Slovak Prime Minister Robert Fico said on Saturday (September 17).
EU leaders met in Slovakia's capital Bratislava on Friday (September 16) at their first summit for decades without Britain after a shock British vote in June to leave the bloc, a subject which Fico said had only been touched on at the meeting.
Fico reiterated that he was opposed to any "cherry-picking" in negotiations, saying EU freedoms must remain.
The Visegrad group (V4) of Central European countries also have a common interest in protecting citizens' rights to work in Britain, Fico said.
"V4 countries will be uncompromising. Unless we feel a guarantee that these people (living and working in Britain) are equal, we will veto any agreement between the EU and Britain," he said.
EU officials on Friday also underlined that there could be no granting Britain access to the EU's single market unless London accepts the freedom of movement of workers that lies at the heart of European Union accord.
Britain has said it would not initiate the formal proceedings this year but it could do so next year, starting a two-year countdown to its exit.
The Brexit vote has triggered what European Commission President Jean-Claude Juncker has described as an "existential crisis" for the EU and Friday's informal meeting of the bloc's 27 members was meant to display unity but instead showed divisions remain over migrant policy.
The EU's eastern members have been at odds with older members, mainly Germany, over taking in a share of more than one million migrants who last year fled war and poverty in Middle Eastern and African countries to come to Europe.