New Secretary of State James Brokenshire has moved to effectively rule out the possibility of a referendum on Irish unity.
Mr Brokenshire told MPs he does not believe that the conditions required to call a border poll have been met.
His comments, made during his Commons debut in his new role, came after Taoiseach Enda Kenny raised the prospect of a future vote on Irish unity in the wake of Brexit.
The Irish premier said EU/UK negotiations should factor in the possibility that a border poll could be held in years to come. But his intervention was dismissed by unionists.
The DUP’s Westminster leader, Nigel Dodds, asked Mr Brokenshire during Northern Ireland questions: “Can you spell out for the benefit of the House once again what you have already said publicly in Northern Ireland, why there is no question of a border poll in Northern Ireland?”
Mr Brokenshire replied: “I have been quite straightforward in relation to the issue of the border poll. The conditions are set out very clearly in relation to the Belfast Agreement and I have been very clear that I do not think those conditions have been met.”
Under the terms of the 1998 Belfast Agreement the power to call a border poll rests with the Secretary of State for Northern Ireland.
But the accord stipulates that such a vote can only be called if there is evidence of a clear shift of public opinion in favour of Irish unity in Northern Ireland.
Mr Dodds said: “The reason, of course, that it hasn’t been met is because the overwhelming majority of people in both communities in Northern Ireland want to remain part of the United Kingdom.
“Do you recognise the irony, the illogicality of those who are talking so much doom and gloom about Northern Ireland and the UK post-Brexit referendum when their main policy, their main raison d’etre, is actually to drag us out of the United Kingdom which would be the most financially catastrophic and politically demoralising thing that is possible to imagine?”
Mr Brokenshire praised the “very special bond that binds the peoples and nations of the United Kingdom together” as he called for people to “come together” to secure a “bright, positive future” for Northern Ireland within the UK.
There was also praise for both former Secretary of State Theresa Villiers and Labour’s former Shadow Secretary of State Vernon Coaker.
Speaking of Ms Villiers, Mr Dodds said that she had “played a constructive and very positive role in Northern Ireland”.