The president-elect’s threat to hit Canada, Mexico and China with new tariffs is already rocking business and diplomatic relationships and could topple the trade pacts he signed in his first term.

While the reaction in US stocks was muted, global equities were rattled. Markets are wondering if Trump's threats are mainly a negotiating tactic.

Senior Canadian figures have reacted with shock and concern to Donald Trump's announcement that he plans to impose tariffs of 25 percent on all goods entering the United States from Canada and Mexico when returned to the White House.