The leaders of Scotland, Wales and Northern Ireland are set to meet in Cardiff on Monday, 13th September, for an unprecedented summit where they are expected to sign a joint declaration calling for their nations to have the right to decide their own constitutional future, fuelling speculation that the UK is headed for a break-up.
The leaders of Scotland, Wales and Northern Ireland will gather on Monday to sign a deal designed to kick-start the break-up of the United Kingdom, The Telegraph can disclose.
— The Telegraph (@Telegraph) September 13, 2026
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The meeting, at the five-star St David’s Hotel overlooking Cardiff Bay, will bring together Scottish First Minister and SNP leader John Swinney, Welsh First Minister Rhun ap Iowerth of Plaid Cymru, and Northern Ireland First Minister Michelle O’Neill of Sinn Féin. Sinn Féin president Mary Lou McDonald will also attend.
The three first ministers are expected to sign a joint declaration supporting self-determination and work together on a new push for constitutional change. Their parties will also sign a memorandum of understanding covering the economy, energy, Europe, international cooperation and self-determination.
Push for independence
The summit comes after Prime Minister Andy Burnham told MPs that another Scottish independence referendum could take place if there was a “clear consensus” for one.
Swinney has since accused Burnham of failing to understand the UK’s constitutional position. He said the fact that Scotland, Wales and Northern Ireland are now led by pro-independence parties shows that the current system is “not sustainable”.
Swinney said Burnham could become “the final prime minister of the United Kingdom” and argued that Westminster should prepare for a future after the UK.
Burnham, however, has rejected the idea of another Scottish referendum before the next general election. In a letter to Swinney, he said there was no consensus in Scotland for another vote and no clear evidence that a majority in Northern Ireland currently wants to leave the UK.
He also pointed to Labour’s 2024 manifesto, which stated that the party did not support independence or another referendum.
Wales seeks more powers
The summit follows Labour’s poor performance in Wales at May’s elections, which saw Plaid Cymru become the largest party in the Senedd. Ap Iowerth subsequently became First Minister.
Plaid Cymru is expected to use the meeting to demand greater powers over Welsh taxes and spending. It wants Wales to receive revenues from the Crown Estate, including the seabed used by offshore wind farms, instead of those funds going to the Treasury.
The party also wants the Barnett Formula replaced with a more generous funding settlement, along with greater control over areas such as policing and rail funding.
Ireland is also part of talks
The meeting will take place shortly after US President Donald Trump said during his visit to Dublin that he would “love” to see a united Ireland, calling Northern Ireland joining the Republic “a great thing”.
Under the Good Friday Agreement, an Irish reunification referendum can be held if it appears likely that a majority in Northern Ireland would vote to leave the UK.
Sinn Féin said the agreement provides a democratic way for people to decide their future and described Irish unity as something that should be prepared for now.
The three parties also plan to support closer links with Europe. Scotland and Wales would seek EU membership as independent countries, while Northern Ireland would join the EU as part of a united Ireland.
The agreement is expected to stress that the parties can gain from working together as equal partners while pursuing their separate constitutional goals.
