A majority of Stormont Assembly members have for the first time voted to legalise same-sex marriage in Northern Ireland, but a voting mechanism triggered by the Democratic Unionists means the law change will not happen.
The vote was the fifth occasion a bid to change Northern Ireland's marriage laws came before the Assembly.
Following the signing into law of same-sex marriage legislation in the Republic last week, Northern Ireland is still the only part of the UK or Ireland where civil marriage is denied to same-sex couples.
A petition of concern was deployed by the DUP ahead of today's vote.
The mechanism means a proposal can only pass if a majority of unionists and a majority of nationalists vote yes.
'Significant milestone'
Campaigners have welcomed the vote today, which saw a majority of Assembly members vote in favour of marriage equality for the first time.
53 MLAs voted for and 51 against a motion which called on the Northern Ireland Executive to introduce marriage equality legislation.
Patrick Corrigan, Amnesty International's Northern Ireland Programme Director, said: "Today's vote is a significant milestone on the journey to marriage equality in Northern Ireland. It shows that, slowly but surely, politicians are catching up with public opinion here, which has been in favour of equal marriage for same-sex couples for some years.
"However, the abuse of the Petition of Concern, to hold back rather than uphold the rights of a minority group, means that Stormont has once again failed to keep pace with equality legislation elsewhere in the UK and Ireland.
"The battle for equality in Northern Ireland will now move to the Courts, where same-sex couples have been forced to go to secure their rights as equal citizens in this country," Mr Corrigan added.
