London (CNN Business) 1. Trump tariff threat: Global stock markets plunged and oil prices fell after President Donald Trump threatened to hike tariffs on Chinese goods.

The move could reignite a trade conflict between the world's two largest economies following months of relative calm in the markets and solid returns for investors.

Trump risked derailing trade talks scheduled for this week by warning on Sunday that he could increase tariffs on $200 billion of Chinese goods to 25% from 10% from Friday.

China's Shanghai Composite plunged 5.6%, while the Shenzhen Composite, which includes many of the country's tech companies, shed 7.4%. The Hang Seng declined 3% in Hong Kong.