China slaps tit-for-tat measures on US as Trump pauses Canada, Mexico tariffs for 30 days

China has slapped tit-for-tat measures on the US and filed a complaint to the World Trade Organization, after Washington's 10% tariffs on Chinese goods came into effect today. China will impose a 15% levy on imports of coal and liquefied natural gas from the US, while crude oil, agricultural machinery, big-engine vehicles and pickup trucks face a 10% duty. Meanwhile, Canada and Mexico have secured a 30-day pause on tariffs after last-minute phone calls with US President Donald Trump. May Wong reports from Hong Kong and Kate Fisher reports from Washington DC.