IT is only “a matter of time” before same-sex marriage is legalised in Northern Ireland, a Scots Labour MP who is pushing to change the law will say today.

Ged Killen, whose husband is from Northern Ireland, where their marriage is not recognised, will make the prediction in the Amnesty International Pride Lecture in Belfast tonight.

The Rutherglen and Hamilton West MP is co-sponsoring a private member’s bill in the Commons to bring Northern Ireland into line with the rest of the UK on gay marriage.

The Northern Ireland Assembly voted for same sex marriage in 2015, but the change was blocked by the DUP using a device known as a ‘petition of concern’, meaning majorities of both Unionists and Nationalists were required for it to succeed.

With the Assembly suspended for 18 months, MPs are urging the UK Government to back legislation which would deliver the change via Westminster instead.

However Theresa May, who relies on the DUP, has refused, saying it is a devolved matter.

Mr Killen said the public in Northern Ireland supported same sex marriage, and there was a ”clear majority” in the Commons and Lords to extend it to the region.

He said: “The opponents of same sex marriage seek to impose a minority view on the LGBT+ community in Northern Ireland through a technicality.

“Under these circumstances, it is anti-democratic not to legislate for same-sex marriage and Westminster has a moral and a democratic obligation to do so.

“For many of us, including myself this is personal as well as political.

"We need to force the Government to change its mind.”

“Theresa May needs to decide whether £1bn and a fragile grip of power is worth perpetuating the ongoing discrimination against the LGBT+ community in Northern Ireland.

“Make no mistake same-sex marriage in Northern Ireland will happen.

“Those who stand opposed risk alienating a generation. The children of future married same-sex couples, their friends and their families will not forgive nor forget those who stood in the way of equality.”