LONDON - British Foreign Secretary Boris Johnson set out his plans for a "glorious" Brexit in a lengthy newspaper article on Saturday that angered colleagues and reignited speculation he would challenge Prime Minister Theresa May for the leadership of the Conservative party.With May due to set out her vision for Brexit in a speech in the Italian city of Florence on Friday, Johnson published a 4,300-word article that roamed well beyond his ministerial brief and, in some cases, went beyond the approach set out by the government.Britain, he said, would not pay to access European markets in the future. Once out of the European Union, the country should borrow to invest in infrastructure, reform the tax code and set immigration levels as it sees fit.A prominent Brexit campaigner in last year's referendum, Johnson also repeated the controversial claim that the government would be 350 million pounds better off per week once outside the EU."My friends, I must report that there are at least some people who are woefully underestimating this country," Johnson wrote in the Daily Telegraph. "They think Brexit isn't going to happen."I am here to tell you that this country will succeed in our new national enterprise, and will succeed mightily."We have a glorious future."