Boris Johnson has stepped up threats to tear up the Northern Ireland Protocol ahead of an expected Bill as early as next week, warning Dublin the crisis is “now very serious”.

       The prime minister told Micheál Martin, the Irish Taoiseach, that “repeated efforts” to reach agreement with the EU had failed – accusing Brussels of failing to take “the steps necessary”.

       Legislation to override the Brexit deal – potentially triggering a hugely damaging trade war with the EU – could be published next week, allies of Liz Truss are suggesting.