The shadow Northern Ireland secretary has said he would call a border poll if the circumstances were right.
Labour MP Peter Kyle said he “would not be a barrier if the circumstances emerge”.
The Northern Ireland Secretary has the power to call a referendum on Irish unity.
While it is not clear what the specific criteria to guide such a decision would be, the Good Friday Agreement states the referendum should be called if it appears likely that a majority of those voting would want Northern Ireland to leave the UK and become part of a united Ireland.
Mr Kyle said he does not believe the issue is affected by last week’s census results which revealed there are more Catholics than Protestants in Northern Ireland for the first time since partition, or Sinn Fein emerging as the largest party at the last Assembly election.
“These are all inter-related aspects of the debate but actually that crucial aspect of when there is a clear majority, which is what was set out in the Good Friday Agreement, that is a different thing altogether,” he told the BBC’s Sunday Politics show at the Labour Party conference.
“If the circumstances emerge as set out in the Good Friday Agreement, I as secretary of state, would not play games. I would call the border poll.
“But these are issues that when you look at the direct needs in Northern Ireland right now – we have a cost-of-living crisis, there is a crisis in public services in Northern Ireland, the longest waiting lists for treatment in the NHS. This is what we’ve got to get on with now.
“So constitutional issues are important but don’t pretend that it is a distraction from the real issues.”
Mr Kyle also said if Labour comes to power and he becomes the secretary of state for Northern Ireland, and it is clear that those circumstances emerge, he would set out the criteria in detail.
We have a small window of opportunity now. We have a new Prime Minister, a new Secretary of State, and we also have a new head of state. I think we have got a great opportunity to really seize the moment and move forward— Peter Kyle
“We’re not even in that circumstance yet, so when we move towards the point where those circumstances set out in the Good Friday Agreement start to emerge and it becomes a priority for the people of Northern Ireland, I will act,” he said.
With speculation that a fresh Stormont Assembly election may have to be called with the institutions remaining unable to fully function due to the DUP’s boycott over the Northern Ireland Protocol, Mr Kyle said more elections will be a “sign of abject failure”.
“It is the job of politicians to solve the problems of residents and voters, it is not the job of voters to solve the problems of politicians,” he said.
“We have a small window of opportunity now. We have a new Prime Minister, a new Secretary of State, and we also have a new head of state. I think we have got a great opportunity to really seize the moment and move forward.”
Meanwhile, questioned on how much time he spends in Northern Ireland, Mr Kyle said he had been in the region twice in the last two months.
He added that since he was appointed to the shadow portfolio in November 2021, he has been many times, including a period where he visited every week for five weeks running.
Mr Kyle said his instinct has always been to get over to Northern Ireland as often as he can, but that depended on how much he is needed in Westminster.
“I would like to be there loads but I don’t have the power as opposition to sit around the table, to convene every political party around there and say, let’s start making progress on this,” he added.
