Slovakia will hold a referendum on same-sex marriage in the predominantly Roman Catholic country on Feb. 7, the president said Thursday.

President Andrej Kiska's move comes after the Alliance for Family conservative group gathered about 400,000 signatures supporting the vote.

Slovaks will be asked whether they agree that a marriage can be called only a union between a man and a woman, same-sex partners can't adopt children, and that children wouldn't have to attend school classes on sex education if their parents don't agree with them.

Slovakia's constitutional court ruled last month at Kiska's request that such a referendum doesn't violate the constitution, but rejected a question on registered partnership as part of the vote.

Kiska said he still has doubts about the referendum, but respected the ruling.

Slovakia doesn't allow same-sex partners to live in registered partnerships and the country's constitution was already amended earlier this year to define marriage as a union between a man and a woman.

To be legally binding, turnout in the ballot must be more than 50 percent in the nation of 5.4 million people. In the previous seven referendums since Slovakia gained independence in 1993 after the split of Czechoslovakia, only the referendum on the country's entry into the European Union met the condition.

Another EU nation, Croatia, banned same-sex marriages in a referendum last year.