A friend writes:
Really sorry to hear this. You are in good company though.....just read that HSBC closed 40 London based diplomatic missions including the apostolic nunciature to Great Britain (papal embassy who had had an account with them for years, like yourself) and Benin and PNG embassies. Also came out of the blue. Apparently a spokesman for the bank said "it had been applying a rolling programme of strategic assessments to all its businesses since May 2011 ... We do not comment on individual customer relationships".