Boris Johnson claimed finally to have settled the vexed question of Britain’s relationship with the European Union as he hailed on Christmas Eve what he called the “jumbo, Canada-style” Brexit deal. At a press conference in Downing Street where he was flanked by two large union flags, the UK’s prime minister said: “This European question’s been going on for decades. I think this gives us the platform, the foundation for a really prosperous new relationship.” He claimed the deal, which will see Great Britain leave the customs union and single market but retain tariff-free access to EU markets, would create a “giant free-trade zone” characterised by “regulatory competition”. The two sides have agreed an independent arbitration process to judge what penalties should be applied if either deviates from current regulatory standards in a way that undercuts the other. Johnson insisted: “We have taken back control of laws and our destiny. We have taken back control of every jot and tittle of our regulation in a way that is complete and unfettered.” He highlighted what he claimed would be the UK’s newfound ability to “set our own standards, to innovate in the way that we want” in key sectors such as biosciences and artificial intelligence. “British laws will be made solely by the British parliament; interpreted by British judges, sitting in the UK courts,” he said. Johnson also stressed the “prodigious” increase in fishing catches he said the UK would now be allowed to keep. Despite the fact exporters will now face increased friction at the border, he claimed he had struck “a deal which will if anything allow our companies and our exporters to do even more business with our European friends”. His optimism contrasts with the expectations of the government’s own independent forecaster, the Office for Budget Responsibility, which expects Brexit to shave 4% off GDP in the medium term. The fishing industry was also disappointed that Johnson had not secured control of the 12 miles of fishing waters off the coast of Britain. Barrie Deas, head of the National Federation of Fishermen’s Organisations, said: “I think what I would say is that there’s a gap between the rhetoric and the delivery … I think the industry will be bitterly disappointed. I think there will be fury about the failure to secure an exclusive 12-mile zone.” Most of Johnson’s themes in his speech, including sovereignty, regulatory independence and fishing, were those close to the hearts of the Brexit-backing MPs who helped him to win the Tory leadership last year. With MPs set to vote on the agreement on Wednesday 30 December, Downing Street has kept Eurosceptic backbenchers closely informed as negotiations developed. After the deal was struck, many said they would await the verdict of a “star chamber” of experts convened by the backbench European Research Group to go through the agreement line by line. The group, consisting of lawyers and politicians including the former Europe minister David Jones, is not expected to publish its conclusions until Monday. The prime minister urged Brexiters and remainers to move on from the divisions that have plagued UK politics since the referendum. “My message to everybody on both sides of that argument in 2016 is I really think now it’s a long time behind us,” he said. He claimed the UK would remain “culturally, emotionally, historically, strategically and geologically attached to Europe, not least through the 4 million EU nationals who have requested to settle in the UK over the last four years and who make an enormous contribution to our country and to our lives”.