President Trump is locked in a tit-for-tat tariff war with Canada, Mexico, the European Union and China in a bid to remake the US economy for the long term – and some early winners and losers have already emerged.

Beijing, which set steep duties on canola, peas and pork, wants Canada and Mexico to resist U.S. pressure to raise tariffs on Chinese goods.

China announced tariffs on Canadian agricultural and food products on Saturday in retaliation for October's decision to impose duties on Chinese-made electric vehicles, steel and aluminium. The Chinese commerce ministry said a 100 per cent tariff would be placed on Canadian rapeseed oil,