SNP and Plaid do deal with Sinn Fein to push break-up of the UK as leaders meet to demand independence votes after Trump backs united Ireland
The leaders of the Scottish National Party, Plaid Cymru and Sinn Féin have signed a "memorandum of understanding" pledging to work together towards breaking up the United Kingdom, in a move announced ahead of a "separatist summit" in Cardiff. First Minister John Swinney called the gathering a "pivotal moment" in the UK's constitutional journey, arguing Scotland, Wales and Northern Ireland should be free to determine their own futures, a stance that drew sharp criticism from unionist politicians who accused the nationalist leaders of prioritising constitutional politics over pressing domestic issues.
The agreement, signed by Swinney, Plaid Cymru's Rhun ap Iorwerth, Sinn Féin's Mary Lou McDonald and Michelle O'Neill, commits the parties to cooperation on the economy, energy and international relations, while declaring that "Westminster's time is coming to an end". The meeting came amid controversy over Donald Trump's comments backing a united Ireland during his visit to the country, remarks he reiterated while dismissing diplomatic criticism. Scottish Conservative deputy leader Rachael Hamilton said most Scots opposed another referendum, while DUP's Emma Little-Pengelly accused O'Neill of overstepping her authority by attending the summit in her capacity as Northern Ireland's joint First Minister.
- SNP, Plaid Cymru and Sinn Féin sign pact backing UK break-up
- Move follows Trump's remarks supporting a united Ireland
- Unionist politicians accuse nationalists of misplaced priorities
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Nationalist parties have long argued that Scotland, Wales and Northern Ireland would be better off governing themselves rather than as part of the United Kingdom. The Scottish National Party (SNP) leads the devolved government in Scotland, Plaid Cymru is a pro-independence party in Wales, and Sinn Féin is the largest party in Northern Ireland, where it shares power with unionist parties under the peace process arrangements. These parties do not always agree on the details of independence, but they share a common goal of ending Westminster's central authority over their nations.
The devolved governments in Edinburgh, Cardiff and Belfast already control many domestic matters, such as health and education, while Westminster retains control over defence, foreign policy and, crucially, whether and when referendums on independence or Irish unification can be held. Any move towards independence would require significant political and legal change, and unionist parties, who wish to keep the UK together, remain firmly opposed. In Northern Ireland, the government is shared between nationalist and unionist parties, which makes the question of Irish unity especially sensitive.
The idea of Irish unification, merging Northern Ireland with the Republic of Ireland, has periodically drawn comment from senior US figures, given the United States' historic role in Northern Ireland's peace process and its large Irish-American population. Such interventions are often seen as significant because they can shift the diplomatic weight behind a debate that is otherwise handled internally by the UK and Irish governments.
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The case for
Advocates of the nationalist parties' cooperation argue that Scotland, Wales and Northern Ireland each have a democratic right to determine their own constitutional future, and that pooling resources and expertise across parties with a shared goal is a legitimate and efficient way to advance that cause. They see the union as one that should persist only by consent, not default, and view coordinated campaigning on shared concerns such as energy and the economy as a practical response to challenges that cross borders. Supporters would add that public statements of solidarity, including any from foreign leaders, are simply part of a long-standing international conversation about self-determination, and do not by themselves compel any outcome.
The case against
Unionist critics argue that repeatedly agitating for fresh referendums, especially so soon after previous votes and amid ongoing cost-of-living and public-service pressures, distracts governments from the practical business of governing and risks prolonging economic and political uncertainty. They contend that the mandate for such votes should rest on clear, sustained public demand rather than party-level pacts, and that most voters in Scotland currently prioritise other issues over another independence poll. Some also raise concern that a jointly elected office-holder, such as Northern Ireland's joint First Minister, should exercise particular care not to appear to use a cross-community role to advance one constitutional position over another, and that external commentary from foreign politicians is an inappropriate basis for domestic constitutional debate.