SHANGHAI, July 14 (Reuters) - China and Hong Kong stocks climbed on Thursday, as tech shares offset weak performances in banking and real estate sub-indexes following cues that jitters in the property sector are spilling over into the financial system.

** China's blue-chip index CSI300 rose 0.5% by the lunch break, while the Shanghai Composite Index gained 0.3%. In Hong Kong, the benchmark Hang Seng Index rose 0.2%.

** The markets are lifted by a surge in tech shares, as investors brushed aside overnight losses on Wall Street after 40-year-high U.S. inflation data fuels bets on faster U.S. monetary policy tightening.

** Shanghai's tech-focused STAR50 Index jumped 2.7%, while Shenzhen's start-up board ChiNext surged 2.6%. Hong Kong's Hang Seng Tech Index gained 1.7%.

** But investors dumped banking and real estate stocks, as a growing number of homebuyers refuse to pay mortgages of delayed projects until construction resumes.

** The "stop mortgage repayment" movement has spread to many Chinese provinces, and involves more than 100 property projects, the official Securities Times reported on Thursday.

** The CSI300 Bank index fell 2.2% at the end of morning trading, after hitting its lowest level since March 2020. Smaller lenders, such as China Merchants Bank and Bank of Chengdu are among the biggest decliners.

"China's property downturn may finally adversely affect onshore financial institutions after hitting the offshore high-yield dollar bond market," Nomura chief China economist Ting Lu wrote.

** Property shares also fell sharply. Indices tracking Chinese developers listed on the mainland and Hong Kong dropped more than 2% each.

** "The mortgage amount involved is currently insignificant, but may spread," wrote Alvin Wong, an analyst at CLSA. "We believe the event might further dampen homebuyer sentiment, and hence, there is a lower chance of a sales recovery in the near term." (Reporting by Shanghai Newsroom; Editing by Sherry Jacob-Phillips)