Arlene Foster is to step down as Northern Ireland's First Minister at the end of June, bowing to pressure from members of her Democratic Unionist Party (DUP) unhappy with her leadership over Brexit and social issues.

Her announcement adds to instability in the British province, where angry young pro-British loyalists rioted in recent weeks over the perceived growing power of Irish nationalists and post-Brexit trade barriers with the rest of the UK.

Foster, who took power in 2016, said in a statement that she would also step down as party leader on May 28. 

Her leadership of Northern Ireland was "the privilege of my life," she said. 

The announcement comes a day after a majority of DUP lawmakers signed a letter seeking a confidence vote in Foster, who many blame for mishandling Brexit negotiations. Foster resisted compromise on the terms of Britain's exit from the European Union when her party wielded huge power in propping up the government of former British prime minister Theresa May. Foster's decision to throw DUP support behind May's successor Boris Johnson then backfired spectacularly when he broke the party's "blood red line."