Canada's retaliatory tariffs on $20bn of US goods take effect

Canada's retaliatory tariffs on imports from the United States have taken effect, escalating the trade dispute between the two countries.

Tariffs ranging from 15 percent to 50 percent will apply to nearly $20bn worth of US imports from 12:01am ET (04:01 GMT) on Tuesday, matching US-imposed levies on Canadian goods including machinery, textiles and consumer products.