Same-sex marriage campaigners in Northern Ireland are to launch legal action against what they claim is “heartbreaking” Government delay.

Partners will be able to tie the knot from early next year following a major liberalisation of the law surrounding gay unions.

But more than 1,200 couples in Northern Ireland who already have civil partnerships will not be able to convert to full married status in the new year under official proposals, lobbyists said.

Amanda McGurk entered a civil partnership with Cara McCann earlier this year before the law change and said she was devastated to learn she could miss out on a dream wedding.

She said: “My heart broke again and I can assure you that I was not the only person in that room whose heart broke and I could feel other hearts breaking right beside me.

“It was absolutely horrific to realise that we had now gotten so close again, to have it ripped away from us and the realisation that, again, some of us were going to be treated as second-class citizens within our own community.”

Ms McCann said: “Just a few weeks ago, I sat in a room in Stormont House with Government ministers and officials and was told that I could become a married woman in the new year. Now the Government has changed its mind.

“Our campaign for equal marriage has always been about rejecting second-class citizenship. We have already won our campaign in Parliament.

“Now we will go to court to ensure the Government does not escape its legal obligation.”

The Northern Ireland Executive Formation Act mandating the change passed into law on October 21.

Under Government plans, same-sex couples in Northern Ireland will be able to apply for a civil marriage, but will not be able to convert an existing civil partnership to a marriage, or get married in a religious ceremony, the Love Equality campaign said.

A same-sex couple in a civil partnership, two Christian couples and a Christian minister will bring the legal challenge.

Ms McGurk said if they had delayed their civil partnership for a year they could be getting married.

“Now we are in the position of being locked into a civil partnership that we never really wanted in the first place because, let’s face it, nobody ever grows up going, ‘when I get civilly partnered I am going to…’, it is always, ‘when I get married I am going to…’.

“We all want to get married when we grow up, we don’t want to be civilly partnered and I don’t want to have a civil partner, I want to have a wife.

“Now we are sitting at the end of a piece of string and nobody knows how long it is going to be until the day that we can actually be married within the law.”

Parliament forced ministers to introduce the change and more public consultation by the Government is due to clarify issues.

Campaigners argue it is already clear in the rest of the UK and there should be no more delay.

Same-sex marriage legislation
Parliament forced ministers to introduce the change and more public consultation by the Government is due to clarify issues (Rebecca Black/PA)

The Rev Chris Hudson, minister of All Souls Church, Belfast – a member of the Non-Subscribing Church of Ireland – said his colleagues in the rest of the UK and the Republic of Ireland could officiate at a same-sex marriage.

He added: “To decide that you will lock couples of faith out of a process that is on offer to heterosexual couples, which is faith marriage, to me seems to be – and I don’t like using this word – but it is discriminatory.

“I am being treated differently as a minister of faith who offers couples from my church marriage, I am being treated differently when it comes to a same-sex couple.”

Northern Ireland’s largest party, the DUP, is opposed to same-sex marriage on religious grounds, arguing that marriage is between a man and a woman and that civil partnerships were already available to same-sex couples.

A vociferous campaign for change to the law has continued.

The issue was one of the sticking points preventing reformation of the collapsed powersharing Executive at Stormont.

A UK Government spokeswoman said: “Parliament passed legislation which requires the Government to put in place legislation to allow for civil same-sex marriage and opposite-sex civil partnership in Northern Ireland by January 13 2020. We are working to meet this deadline.”