The Shanghai Composite fell 0.2% to below 3,345, while the Shenzhen Component dropped 0.9% to 10,510 on Monday, extending losses from the previous session as investors braced for new US tariffs set to take effect this week.

Over the weekend, President Donald Trump stated he "couldn't care less" if foreign automakers raise prices in response to the tariffs, while The Wall Street Journal reported that he is pressuring advisors to take a more aggressive stance on trade policies.

Meanwhile, data showed that China's manufacturing activity expanded at its fastest pace in a year in March, while services sector growth hit a three-month high. The latest PMI figures signaled that Beijing's stimulus measures are supporting economic recovery, though weak domestic consumption and global trade tensions remain key risks. High-growth technology and new energy stocks led the decline.

Source: Trading Economics