Deepening uncertainties over the direction and timetable of Brexit negotiations may force Toyota (7203.T) to shift some UK production elsewhere if they are not addressed, the Japanese carmaker warned on Tuesday.Early government assurances that free trade with the European Union would survive Britain’s departure have been replaced by talk of transition periods, Toyota Executive Vice President Didier Leroy told Reuters.“A few months ago the UK government was saying, ‘We’re sure we’ll be able to negotiate (a deal) without any trade tax,'” Leroy said in an interview at the Frankfurt car show. “They are not saying that any more.”He added: “It’s clear that if we have to wait two to three more years to have a clarity on this topic, we will have a big question-mark about our future investment in the country.”