Tuesday’s planned vote on equal marriage has been vetoed by the Democratic Unionist Party.
The DUP has once again tabled a petition of concern, using Assembly rules to effectively ban cross-party discussion of the measure.
It will frustrate Sinn Fein, the Social Democratic and Labour Party (SDLP), the Alliance Party, NI21 and the Greens, who all support equal marriage.
The DUP has continually resisted supporting LGBT equality across the board. First Minister Peter Robinson and Health Minister Edwin Poots have refused to lift Northern Ireland’s lifetime ban on gay and bisexual men giving blood.
Demonstrations by equal marriage campaigners took place in Northern Ireland last month on the eve of the first same-sex marriages in England and Wales in order to highlight the equality gap in the province.
Same-sex marriages conducted in England and Wales are currently only recognised as civil partnerships.
Amnesty International has said equal marriage in Northern Ireland could eventually be secured in the courts – in order to bypass the DUP’s opposition.