Northern Ireland's First Minister Paul Givan resigned in protest at post-Brexit trade rules on Thursday, a day after one of his pro-British colleagues attempted to halt some checks on goods, drawing anger from European Union member states.
"Today marks the end of what has been the privilege of my lifetime," Givan, who spent less than a year in the role, told a news conference.
The British government's Northern Ireland minister Brandon Lewis said Givan's decision to resign was "extremely disappointing".
As part of its Brexit deal, Britain agreed a document known as the Northern Ireland protocol with the European Union that aims to avoid politically contentious border checks between British-ruled Northern Ireland and EU-member Ireland.
But the protocol has effectively created a border in the Irish Sea for goods moving to the province from Britain because it kept Northern Ireland in the EU's single market for goods.
This has angered pro-British unionists and prompted London to seek to rewrite the deal it signed up to before it left the EU in 2020.
(FRANCE 24 with REUTERS)