The head of the Bundesbank appealed to Britain on Wednesday to stay in the European Union, saying membership of the bloc had given the country an economic lift and posed little threat to London. In a speech to business people and bankers in central London, Jens Weidmann broke the central bank’s traditional silence on political questions, saying the European Union would benefit if Britain “continues to make its voice heard”. “The EU is stronger today because of Britain’s contribution to it,” Weidmann said, adding that the country’s trade with EU neighbors had been boosted by more than half because of...