London - Foreign Secretary Boris Johnson has called for Britain to completely throw off EU rules and to view Brexit as an opportunity, while refusing to deny he might quit if the government chose a different path.
Johnson, a leading campaigner behind Britain's vote to leave the European Union, used a speech in London to try to reassure the millions of Britons who wanted to stay by offering a positive vision of Brexit.
He said the project's success "will depend on what we make of it" -- and said it would be "absurd" if Britain left the bloc only to align itself with all its rules in future, without having any say in them.
"We would be mad to go through this process of extrication from the EU and not to take advantage of the economic freedom it will bring," he said in a highly-anticipated speech at a think tank in London on Wednesday.
"In a global marketplace... it seems extraordinary that the UK should remain lashed to the minute prescriptions of a regional trade bloc comprising only six percent of humanity," he added.
His call for a clean break with Brussels puts Johnson at odds with other members of Prime Minister Theresa May's cabinet, not least her finance minister Philip Hammond, who wants Britain's economy to diverge only "modestly" from the EU.
Johnson dodged a question about whether he might resign if he disagrees with any deal struck with Brussels later this year, saying only: "We're all lucky to serve."
His speech was the first of series of high-profile ministerial addresses on Brexit, as May's divided government prepares for crucial talks with Brussels on the future trading relationship starting from April.
- 'Overarching European state' -
Johnson, viewed as a potential successor to May, has challenged her authority over Brexit several times, and admitted Wednesday that he risked causing some "irritation" with his latest speech.
But said he felt the need to "reach out to those who still have anxieties" about the 2016 vote to end four decades of EU membership.
Pros and cons of possible models for a post-Brexit relationship between the UK and the EU
He stressed that Britain had not turned in on itself, saying with typical flourish: "It's not some great V-sign from the cliffs of Dover."
He said the vote was driven by a "legitimate and natural desire for self-government", which was at odds with what he said was the EU's main goal of creating "an overarching European state".
Johnson's comments prompted a swift response from European Commission chief Jean-Claude Juncker, who said the idea of a European superstate was "total nonsense".
He also risked antagonising some of those he aimed to reassure by falling back on phrases used by the anti-Brexit side, saying that trying to stop the process would "frustrate the will of the people" and lead to "ineradicable feelings of betrayal".
Johnson also firmly rejected the idea of a second referendum, saying it would lead to "another year of turmoil and wrangling and feuding, in which the whole country would lose".
- 'Project Fantasy' -
Wednesday's speech kicks off a series of coordinated ministerial addresses, which will include one by May on security issues in Munich on Saturday.
Three other key cabinet ministers will follow over the subsequent two weeks, after which May will make a second address to the nation.
Emphasising the benefits of leaving the EU, Johnson repeated a highly contested claim from the referendum campaign that Britain could use some funds currently sent to Brussels to pay for its state-run health service.
Britons could also "fish our own fish", cut sales-tax on domestic fuel and develop new regulations on stem cell technology, he said.
However, he was accused of failing to be honest with the public about any economic consequences of leaving the EU's single market and customs union.
"The scaremongering, mistruths, lack of detail and utter disregard for the economic realities of Brexit were an alarming throwback to the referendum campaign," said opposition Labour lawmaker Chuka Umunna.
"More than 18 months since the referendum, this was simply more of the same Project Fantasy."
By Alice Ritchie