LONDON (AP) - British Prime Minister Boris Johnson talked tough on Sunday ahead of a crucial round of post-Brexit trade talks with the European Union, saying Britain could walk away from the talks within weeks and insisting that a no-deal exit would be a "good outcome for the U.K." With talks deadlocked, Johnson said an agreement would only be possible if EU negotiators are prepared to "rethink their current positions." The EU, in turn, accuses Britain of failing to negotiate seriously. Britain left the now 27-nation EU on Jan. 31, three-and-a-half years after the country narrowly voted to end more than four decades of membership. That political departure will be followed by an economic break when an 11-month transition period ends on Dec. 31 and the U.K. leaves the EU's single market and customs union. Without a deal, the New Year will bring tariffs and other economic barriers between the U.K. and the bloc, its biggest trading partner. Johnson said the country would "prosper mightily" even if Britain had "a trading arrangement with the EU like Australia's" - the U.K. government's preferred description of a no-deal Brexit. British chief negotiator David Frost and his EU counterpart Michel Barnier are due to meet in London starting Tuesday for their eighth round of negotiations. Barnier said last week he was "worried and disappointed" by the lack of progress and said the U.K. had not "engaged constructively." The key sticking points are European boats' access to U.K. fishing waters and state aid to industries. The EU is determined to ensure a "level playing field" for competition so British firms can't undercut the bloc's environmental or workplace standards or pump public money into U.K. industries. Britain accuses the bloc...