Almost three quarters of people in the UK believe gay couples should be able to marry in Northern Ireland, a survey showed.
It is the only part of the country where same-sex marriage is illegal.
Supporters of change want Westminster to legislate in the absence of devolved powersharing at Stormont.
Northern Ireland’s largest party, the Democratic Unionists, believe marriage is between a man and a woman and argue civil partnerships are available to same-sex couples.
Gay rights activist John O’Doherty said: “Justice delayed is justice denied.