The BBC reports:

From Monday, same-sex couples will be able to register to marry, meaning the first ceremonies will take place in February. For couples who are already married, their marriage will now be legally recognised in Northern Ireland.

However, those who are already in a civil partnership will not be able to convert it to a marriage at this stage. The Northern Ireland Office is set to begin a consultation later this year about converting civil partnerships and the role of churches in same-sex marriages.

Same-sex marriages have been allowed in England, Scotland and Wales since 2014, but Stormont did not legalise them. In November 2015, a vote on the issue in the devolved assembly resulted in a numerical majority in favour of same-sex marriage for the first time. However, the DUP blocked a change in the law by using a veto known as the Petition of Concern.