Leaders from the Czech Republic, Hungary, Slovakia and Poland have rejected what they call Brussels' use of "blackmail and diktat" over planned resettlements of migrants across the European Union. Protesting suggestions that the level of their compliance could be linked to the availability of EU funds to them, the four eastern EU states ruled out any links between accepting them and future disbursements of EU funds.

Eastern EU states "will never accept blackmail and diktat" on migration policy, Polish Prime Minister Beata Szydlo said at a press conference in Warsaw with her Czech, Hungarian and Slovak counterparts.

Czech Prime Minister Bohuslav Sobotka insisted that all four countries "oppose linking the debate about migration to European funds."

"This is blackmail, that we reject in the name of the Slovak government," added Slovak Prime Minister Robert Fico.

A meeting in Warsaw of the so-called Visegrad Group brought together Poland's Szydlo and her counterparts from Hungary, Slovakia and the Czech Republic. Their talks included the EU's migrant policies and its 2015 plan of sharing some 160,000 refugees among member states to ease the pressure on Greece and Italy. The Visegrad Group aspires to play a greater role in EU policies while at the same time makes a point of criticizing the bloc's decisions.

This month, the EU warned that countries could be punished if they fail to share the burden, raising the possibility of fines against member states.

Central European leaders said they reject the relocation plan and will not yield to financial pressure, which they called an attempt at blackmail. Poland's government is citing security concerns among the reasons behind its refusal to take in people.

Hungarian Prime Minister Viktor Orban said his country was further sealing its borders and tightening regulations to block access to any more migrants, saying that the action serves the security of all of Europe. Orban says the regulations would enable Hungary to stop migrants on its southern border with Serbia. The United Nations and human rights advocates have criticized Hungary's new detention policy as inhumane. Orban says the regulations promote the "security of EU citizens."

"We are defending Hungary, we are defending the countries behind us and we can say that Austrians and German can sleep in peace," he added.

In addition to the Central European countries, Austria said it wants to withdraw from the refugee relocation deal. Austria's chancellor says he will push in Brussels for at least temporary exempt status from an EU-wide plan to distribute refugees.

The agreement will run out in September. So far, fewer than 15,000 people have been transferred within the EU. EU members have until September to take in 160,000 refugees from Syria and elsewhere currently living in Greece and Italy, which have been on the frontline of the migration crisis. So far only 13,500 have been relocated in a laborious process that has been bogged down by resistance from central and eastern European states that oppose Muslim immigration. The EU launched the relocation scheme in September 2015 to deal with the biggest wave of refugees in its history, with more than 1.1 million arriving in 2015, most of them fleeing the conflict in Syria.