By Promit Mukherjee and David Ljunggren OTTAWA (Reuters) -Ex-central banker Mark Carney was formally sworn in as prime minister of Canada on Friday, putting him in a position to fight tariffs from U.S.

Former Bank of England governor Mark Carney was sworn in as Canada’s new prime minister on Friday, and will now try to steer his country through a trade war brought by US President Donald Trump, a threat of annexation and an expected federal election.