China stocks suffered their worst one-session loss in more than two years, as Asian stock markets plunged Monday on fears trade negotiations between the U.S. and China were on the verge of collapse.

On Sunday, President Donald Trump tweeted that he would raise tariffs on $200 billion of Chinese goods from 10% to 25% this week, apparently taking Chinese officials by surprise. In response, China may withdraw from the next round of trade talks scheduled to begin Wednesday in Washington. U.S. officials had indicated progress had been made at talks last week in Beijing, and said it was possible a deal could be reached by the end of this week.