Former UK prime minister Boris Johnson says he would find it "very difficult" to vote for successor Rishi Sunak's new EU deal overhauling post-Brexit trade rules in Northern Ireland. Johnson, whose supporters accuse Sunak of betrayal for having helped force the former leader out last year, broke his silence after the breakthrough deal was announced on Monday. "I'm going to find it very difficult to vote for something like this myself, because I believed that we should have done something very different," Johnson says in the speech in London. IMAGES AND SOUNDBITES