Chinese shares were mixed on Tuesday as investors adopted a cautious stance ahead of the Trump-Xi summit and slowing approvals for initial public offerings of robot companies.

The Shanghai Composite Index, the main gauge of Chinese stocks, ticked up 2.22 points at 3,952.13. The Shenzhen Component Index slid 6.29 points to 13,723.74.

Investors are holding back on major positioning until they see whether the expiring trade truce will be extended and how Beijing and Washington will handle export controls, rare-earth supplies and artificial intelligence policy.

Separately, China is hindering the progress of humanoid robot companies applying for initial public offerings due to retail-investor concerns. Market regulators have used informal "window guidance" to slow down the listings of such companies, effectively freezing them, although there is no formal ban.

In company news, Greenland Holdings (SHA:600606) said its overdue debt rose to 33.7 billion yuan as of mid-September, with 715 million yuan added from Sept. 2 to Sept. 19. The real estate and infrastructure company also faced 1,110 new lawsuits totaling 3.92 billion yuan during the same period. Shares of the company closed 4% lower Tuesday.