The Slovak Interior Ministry has prepared an amendment to the electoral law which opposition leaders say is a blatant attempt to ruin their chances in September's general elections.
The Interior Ministry said on Thursday it had prepared a draft which would require each party within a coalition to cross a five percent threshold of the overall electoral vote in order to gain parliamentary representation.
"The change to the quorum (threshold) was decided to give equal chances for all political subjects in the election," said Dušan Sveda of the Interior Ministry's legal department.
The current law contains no such provision, requiring only that coalitions of more than three parties obtain 10 percent of the vote while single parties, running independently, must obtain five percent.
The Slovak Democratic Coalition (SDK), a loose alliance of five opposition parties, which holds a commanding lead over Prime Minister Vladimir Mečiar in the opinion polls, said the move was an attempt to thwart their chances.
"This move is clearly aimed at the SDK and even kills two birds with one stone, as it would hit the ethnic Hungarian coalition (MK) as well," Ludovit Černak, vice-chairman of the Democratic Union, an SDK member party, told Reuters.
Černak said the two strongest members of SDK, the Democratic Union and the Christian Democratic Movement, may have to allow members of smaller SDK parties, which risk elimination because of the draft, to run on their slates.
An opinion poll conducted in the middle of January put the combined support of opposition parties at 54.8 percent, compared to 36.4 percent for the three-party coalition government whose parties stand independently.
However, 32.5 percent of the opposition's overall support comes from the SDK and a further 10.9 percent from the three-party Hungarian coalition (MK).
Apart from changes to the law on coalitions, the amendment also contains a vaguely worded clause banning electoral campaigning in the privately owned media.
"According to the draft, electoral campaigning in these (private) media...would be banned," said Interior Ministry official Jozef Liska.
Neither Liska nor Sveda would explain what was meant by "electoral campaigning." Slovakia's privately owned media are frequently accused by Prime Minister Mečiar of bias against the government.
The law has a strong chance of passing in Parliament because it needs only a simple majority in the 150 seat assembly. The government has 81 seats.