But tensions were tempered when Ontario premier made a deal with US commerce secretary to roll back 25% levy on electricity exports

• US politics – live updates

The looming trade war between the US and Canada escalated on Tuesday as Donald Trump threatened to double tariffs on Canadian steel and aluminum after Canadian threats to increase electricity prices for US customers.

On Tuesday morning Trump announced plans to double tariffs on Canadian steel and aluminum from 25% to 50% and once again threatened to annex Canada as retaliation for the province of Ontario’s imposition of a 25% surcharge on electricity exports to several US states, in a dramatic escalation of the trade war between the two ostensibly allied countries.