SHANGHAI, May 18 (Reuters) - China stocks were largely flat while Hong Kong shares declined on Monday as investor focus shifted from U.S.-China leaders' two-day meeting to escalating tensions in the Middle East and a global bond selloff.

** In early trade, the Shanghai Composite Index .SSEC and China's blue-chip index CSI300 .CSI300 held their ground at roughly 4,136 and 4,847 points, respectively.

** Hong Kong's benchmark Hang Seng Index .HSI led losses across Asian markets, down 1.4%, mirroring an overnight decline on Wall Street.

** Market sentiment weakened after fresh attacks in the Gulf pushed oil prices and bond yields higher.

** A drone strike caused a fire at a nuclear power plant in the United Arab Emirates, while Saudi Arabia said it intercepted three drones. U.S. President Donald Trump also warned Iran to move "fast" on a deal.

** Investors are increasingly concerned that central banks may tighten policy further to contain inflation pressures, overshadowing the Trump-Xi summit, which produced limited concrete outcomes.

** "In our view, the summit delivered short-term stabilization for both leaders," Nomura economist Lu Ting said, referring to a new paradigm described by Washington as a pragmatic arrangement and by Beijing as a "Constructive Strategic Stability U.S.-China Relationship".

** "We believe the summit is overall a success, though it might disappoint some people that had too high expectations right before the summit."

** China-listed agriculture stocks fell more than 2% after the White House said Beijing committed to buying at least $17 billion worth of U.S. agricultural products annually from 2026 to 2028.

** Meanwhile, Chinese chipmakers .STARCHIP rose after U.S. officials indicated semiconductor export controls were not a key issue during talks in Beijing, suggesting any breakthrough on Nvidia's NVDA.O H200 chip sales to China remains distant.