The first ministers of Scotland, Wales and Northern Ireland will hold an unprecedented summit in Cardiff on Monday to discuss greater self-determination and possible constitutional change for the three nations.
Scottish First Minister John Swinney, Welsh First Minister Rhun ap Iowerth and Northern Ireland First Minister Michelle O’Neill are expected to sign a joint declaration affirming the right of their nations to decide their own constitutional futures, including the option of independence referendums.
Sinn Fein president Mary Lou McDonald, who leads the opposition in the Republic of Ireland, will also attend the meeting at the St David’s Hotel overlooking Cardiff Bay.
The leaders plan to discuss cooperation on the economy, energy, Europe, international relations and self-determination.
The gathering comes as pro-independence parties now head the governments in all three nations. The Scottish National Party remains dominant in Scotland, Plaid Cymru became the largest party in the Welsh Senedd after May’s elections, and Sinn Fein has held the Northern Ireland First Minister’s post since 2024.
Swinney described the political landscape as clear evidence that the current UK arrangement is unsustainable.
“For the first time ever, Scotland, Wales and Northern Ireland are led by pro-independence first ministers. There could be no clearer sign that the status quo is not sustainable – and that Westminster must prepare for a post-UK future,” Swinney said.
He added: “The momentum behind serious constitutional change is undeniable. Andy Burnham must now be facing up to the idea that he will go down in history as the final prime minister of the United Kingdom.”
The parties are also expected to back closer ties with the European Union, with Scotland and Wales potentially seeking membership as independent states and Northern Ireland joining as part of a united Ireland.
A Plaid Cymru source said the three parties had “a strong case for practical political cooperation” on shared interests.
Sinn Fein sources indicated the summit would advance preparations for Irish reunification, citing the Good Friday Agreement as the democratic mechanism.
“The Good Friday Agreement gives us the democratic means to decide it, and now is the time to prepare seriously for that choice,” a party source said. “Irish unity is not a distant aspiration. The work of building the new Ireland must begin now.”
The leaders are due to hold a joint press conference after the meeting.
