The first ministers of Northern Ireland, Scotland and Wales united Monday behind calls to leave the United Kingdom in an unprecedented alignment of nationalist leaders.
Why it matters: For the first time, all three first ministers favor leaving the U.K. — and Northern Ireland First Minister Michelle O'Neill says President Trump's support for a united Ireland has taken the debate global.
Driving the news: The nationalist leaders of the Scottish National Party, Sinn Féin and Plaid Cymru met in Cardiff, Wales, on Monday to sign a memorandum of understanding declaring that the "political landscape across these islands is changing."
What they're saying: "For people watching across these islands – for people watching around the world – there could be no clearer sign that Westminster's time is coming to an end," the memo said.
Zoom in: O'Neill told reporters that Trump's support for Irish reunification during a two-day visit over the weekend reflected a "growing conversation around constitutional change at home in Ireland."
Yes, but: A spokesperson for U.K. Prime Minister Andy Burnham has said Trump's comments don't change his stance that it's premature to call for independence referenda until public opinion clearly shifts.
The other side: Trump's comments drew backlash from British lawmakers and unionists, including Northern Ireland's Deputy First Minister Emma Little-Pengelly who criticized O'Neill's attendance at the summit in an interview with the BBC.
Go deeper: Why Trump's united Ireland stance hit such a nerve