The Chinese government has accused the US of "double standards" following Donald Trump's latest tariff threat.
China insisted it was "not afraid" of a trade war as it threatened "countermeasures" after Trump warned he could impose an additional 100% tariff in Chinese goods.
On Friday, Trump responded to Beijing's move to tighten its rules for rare earths exports, accusing it of "becoming very hostile".
He also threatened to pull out of a meeting with China's President Xi Jinping later this month, the BBC reports, before reassuring markets on social media Sunday, saying: "Don't worry about China, it will all be fine!"
Trump's comments on Friday rattled financial markets, with the S&P 500 share index closing down 2.7%, its steepest fall since April.
On Monday, the Shenzhen Component Index in mainland China was down by more than 2.5%, while Hong Kong's Hang Seng was around 3.5% lower.
FTSE100
The UK's flagship share index, the FTSE 100, was down 45 points at 9,452 shortly after opening this morning.
Brent crude oil futures were up 0.35% at $63.59 a barrel.
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