Nationalist leaders of Scotland, Wales, and Northern Ireland sign pact demanding self-determination from UK

Joint declaration in Cardiff

The leaders of the ruling nationalist parties in Scotland, Wales, and Northern Ireland met in the Welsh capital of Cardiff on Monday to sign a joint memorandum of understanding asserting their right to self-determination. The gathering brought together Scottish First Minister John Swinney of the Scottish National Party, Welsh First Minister Rhun ap Iorwerth of Plaid Cymru, and Northern Ireland First Minister Michelle O'Neill alongside party president Mary Lou McDonald of Sinn Féin. The leaders signed the document in their capacities as party chiefs rather than government executives, issuing a formal challenge to the central administration in London.

“Andy Burnham will be the last prime minister of the United Kingdom, because the people of Scotland, if given the choice of independence in a referendum, will take that choice.”

Devolution and diverging constitutional paths

The Cardiff meeting is the first time since the devolution process began in 1999 that pro-independence parties simultaneously hold power in all three devolved UK administrations. Devolved parliaments oversee regional public services, including healthcare, education, housing, transport, environmental regulation, and specific tax powers. The joint text emphasizes that no Westminster government has the right to block democracy or prevent local populations from deciding their own future, stating that the long-term future of all three nations belongs inside the European Union.

Despite the unified declaration, each party pursues distinct mechanisms and timelines for departing the union. Swinney continues to demand a second referendum after Scotland voted to remain in the United Kingdom in 2014. Sinn Féin maintains its push for a border poll to merge Northern Ireland with the Republic of Ireland. In Wales, where Plaid Cymru won regional elections in May, ap Iorwerth declined to set a referendum schedule, agreeing that each nation must determine its path on its own timetable. In addition to constitutional declarations, the leaders established practical policy partnerships across renewable energy, economic development, and direct European engagement, with Scotland and Wales preparing a separate bilateral cooperation agreement.

Political responses in London, Dublin, and Washington

The initiative faced condemnation from UK-wide opposition and governing figures. Representatives from both the Labour Party and the Reform Party criticized the gathering, accusing Plaid Cymru of attempting to dismantle the union. The Cardiff summit occurred two days after US President Donald Trump endorsed the dissolution of the UK during a visit to Ireland on Saturday, remarking that a breakup would be a great thing.

McDonald defended Trump's statements to reporters, pointing to traditional American sympathy for Irish unification. In Dublin, Irish Taoiseach Micheál Martin of Fianna Fáil rejected fast-track unity proposals during an interview on RTÉ radio on Monday. Martin warned against simplistic rhetoric and cautioned against references to 1970s-era republican positions, referencing the conflict period where the Provisional Irish Republican Army killed nearly 1,800 people before its 1997 ceasefire.

“I believe in Irish unity, but I want an Irish unity that works. That takes hard work. I'm not into simplistic rhetoric.”