LONDON — The U.K. government is in negotiations with Canada over joining its NATO-linked defense bank, and membership of a global fighter jet program, Canada’s top diplomat in Britain said. In an interview with POLITICO, Bill Blair, the Canadian High Commissioner to the U.K., said that Gordon Brown has spoken directly to the country’s premier, Mark Carney, about the Defence, Security, and Resilience Bank (DSRB). There are “conversations taking place” between DSRB officials and both the U.K.