Both candidates to replace Theresa May as prime minister, Boris Johnson and Jeremy Hunt, have said that they would be prepared to pursue a no-deal Brexit if necessary and have ruled out accepting an Irish backstop, an insurance policy to prevent the return of border controls in Ireland.

"I followed what was said last night in relation to the contenders for leadership of the Conservative Party ... The Irish government and the EU are really clear that we will not be changing the content of the backstop agreement," Donohoe said.