… remedy for Irish “backstop” When he spoke in front of 10 Downing Street for the first time as prime minister on … Johnson made it clear the UK will leave the EU on Oct. 31, with or without a deal: “We are going to fulfil the … before Dec. 31, 2020 or, with an extension, Dec. 31, 2021 or Dec. 31, 2022] as part of the future relationship. …