London (CNN Business) 1. Trade overhang: Investor concern that the United States and China won't resolve their trade fight any time soon is driving markets lower, setting the stage for another volatile week.

US stock futures also spell trouble. The Dow is poised to drop about 300 points at the open, or almost 1.2%. The Nasdaq is set to fall 1.6%, while the S&P 500 is tracking down 1.2%.

Front of mind is a warning Sunday from Larry Kudlow, President Donald Trump's top economic adviser. He said US officials expect China to retaliate for the tariff hike the Trump administration imposed on Friday, when it increased import taxes on $200 billion of Chinese goods to 25% from 10%.

"We'll see what they come up with," Kudlow said of Beijing's expected response.

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