Speaking on national television, Slovak Prime Minister Robert Fico said his country might follow the Czechs should they demand an opt-out from the Lisbon Treaty concerning the Charter of Fundamental Rights.
If the opt-out is granted only to the Czech Republic, Slovakia fears that it could "remain in legal uncertainty," Fico explained.
Peter Stan, a spokesman for the Slovak Foreign Ministry, told national news agency TASR that "Slovakia, like the Czech Republic, is the successor of Czechoslovakia, and the Beneš Decrees are part of our legal system. The Lisbon Treaty can not be allowed to give different legal certainties to two successor states in respect of the Decrees".
The Beneš Decrees forcibly expelled 3 million ethnic Germans from what was then Czechoslovakia at the end of World War II because of the majority's support for the Nazis.
Slovakia's foreign ministry stressed that the country has already ratified the treaty without any additional requirements, but due to the demands of the Czech president "we have become, against our will, part of the process".
It is expected that the final wording of the Czech - and now also, perhaps, the Slovak – demands will be made at the October EU summit of heads of state and government in Brussels.
Slovak demands may strengthen EU's resolve against Klaus
It is not yet clear what exact demands the Czechs will make in respect of the Beneš Decrees. Czech Prime Minister Jan Fischer indicated that one option would be for EU leaders to approve a political declaration addressing Klaus's concerns at the summit, and commit themselves to put it as a footnote to the treaty at some point in the future.
However, Klaus wants a full opt-out from the EU Charter of Fundamental Rights - part of the document - similar to that obtained by the UK and Poland in negotiations two years ago.
Sources told EurActiv that the latter scenario could be problematic, as some EU governments are reluctant to grant Klaus even a political declaration.
Indeed, a European Commission source told EurActiv Slovakia that the EU executive was aware that Fico would be forced to follow suit regarding Beneš, and his declaration yesterday will be used as a bulwark to increase pressure on EU leaders not to submit to Klaus's demands.