In the decision, announced on Friday, the top court agrees with the initiator of the review, the Administrative Court, that current provisions fail to put same-sex couples on par with heterosexual partners, who can marry outside of official premises.

Giving parliament six months to remedy the situation, the Constitutional Court said same-sex partners should be allowed to register outside of administrative units if they put forward important reasons for this.

The decision comes after the Constitutional Court allowed in 2012 and 2015 referendums on legislation introducing gay marriage. In the last vote in December last year, opponents of gay marriage and adoption defeated gay marriage with 63.5% of the vote.

Slovenia introduced civil unions for same-sex couples in 2005, but this does not provide for many of the rights afforded to married couples, including on inheritance and visitation rights. The inheritance issue was acknowledged by the Constitutional Court in 2009 and again in 2013.