Celtic first ministers tell London to plan for constitutional change

The first ministers of Scotland, Wales and Northern Ireland met in Cardiff on Monday and signed a memorandum of understanding that says constitutional change is coming. John Swinney of the Scottish National Party, Rhun ap Iorwerth of Plaid Cymru, Michelle O'Neill of Sinn Fein and Sinn Fein president Mary Lou McDonald declared that the nations they represent have a right to self-determination and that no Westminster government has the right to block it.

The text states that, for the first time, people across these islands have first ministers in Scotland, Wales and the North of Ireland who are all committed to independence from the United Kingdom. It calls on the British government to prepare for, plan and facilitate constitutional change in each jurisdiction. It also says the future of those nations belongs in the European Union.

Party hats, not government letterhead

The four leaders met as party officers, not as a joint session of their administrations. That distinction matters in Belfast. Northern Ireland's deputy first minister, Emma Little-Pengelly of the Democratic Unionist Party, said O'Neill had not sought agreement or permission to travel, attend or sign anything as first minister. The Belfast institutions require the first and deputy first ministers to act jointly on many matters. A Sinn Fein signature on an independence memorandum is a party act. Unionists will treat it as a government slight anyway.

The timing follows Plaid Cymru's win in the Senedd elections in May, which put separatist parties in charge of all three devolved governments at once. Swinney and O'Neill speak openly about referendums. Ap Iorwerth has ruled out pushing for a Welsh vote now. The memorandum papers over that gap with a shared claim of principle and a list of practical files: jobs, energy, and work with Europe.

President Donald Trump's recent remark in favour of Irish unity hung over the meeting. Irish and British politicians have spent days arguing about whether an American president should say that. The Cardiff text does not mention Trump. It does mention Brussels.

What the document can and cannot do

A memorandum of understanding between parties does not dissolve the United Kingdom. The Supreme Court in London has already held that Holyrood cannot legislate for a second Scottish independence referendum without Westminster's consent. Wales has no equivalent statute. Northern Ireland's path runs through the Good Friday Agreement, which sets a different test for a unity poll and gives the Secretary of State, not Stormont, the power to call one.

The political fact the signatories want to advertise is simpler. Three governments that used to split between nationalists and unionists or between nationalists and Labour now have nationalist first ministers at the same time. They intend to coordinate pressure on Downing Street and to present independence as a shared European project rather than three separate quarrels.

That framing has costs. English public opinion, which still decides the Commons arithmetic, has little patience for a coordinated break-up. The DUP and other unionists in Northern Ireland will use the Cardiff text to argue that Sinn Fein is campaigning against the state it jointly administers. In Scotland, Swinney still has to win a Westminster concession he has not won before. In Wales, ap Iorwerth has to grow support for independence that remains well below the Scottish figure.

The sentence that will be quoted

The line written for the cameras was that Westminster's time is coming to an end. The operational sentence is the request that the British government prepare, plan and facilitate change. London's likely answer is that the union is a matter for the whole United Kingdom and that no such planning is under way. The four signatories knew that when they sat down. The meeting was a marker, and a test of whether three different independence projects can share a table without agreeing a timetable.