Nationalist Leaders Sign Cardiff Pact to Pressure UK for Independence

Pro-independence leaders from Scotland, Wales, and Northern Ireland met in Cardiff on September 14, 2026, to sign a memorandum of understanding, also known as the Cardiff Pact. John Swinney of the Scottish National Party, Rhun ap Iorwerth of Plaid Cymru, and Michelle O'Neill of Sinn Féin signed the agreement to pressure the British government to facilitate independence referendums and constitutional change. The leaders declared that "Westminster’s time is coming to an end" and pledged cooperation on renewable energy, economic growth, and re-entering the European Union.

The summit followed a political shift in May that placed pro-independence parties in power across all three devolved regions. The push for separation was further intensified by U.S. President Donald Trump, who expressed support for Irish reunification during a visit to Ireland, describing it as "one of the naturals of all time."

UK Prime Minister Andy Burnham rejected the demands, stating that referendums remain "off limits" and that he believes "strongly in the Union." In Northern Ireland, Deputy First Minister Emma Little-Pengelly accused O'Neill of attempting to "weaponise the role of First Minister," though Sinn Féin President Mary Lou McDonald clarified that O'Neill attended as a party leader. In Ireland, Taoiseach Micheál Martin criticized the alliance, suggesting that embroiling Northern Ireland in British politics could set back the cause of Irish unity.

Beyond the main pact, Swinney and ap Iorwerth signed a separate Cardiff Agreement to collaborate on child poverty and climate change. In response to the escalating tensions, the UK government announced a summit with the three regions will be held in October.