CHINESE airlines will be suspended from operating new flights or raising frequencies to Shanghai, Beijing and Guangzhou, the country's busiest hubs, in the winter-spring season because of limited landing slots and worsening flight delays, the aviation regulator said.

Only flights that can help improve the connectivity of the three cities will be allowed, the Civil Aviation Administration of China said in a statement on its website yesterday.

The CAAC also encourages airlines to use larger aircraft to serve the three cities instead of increasing frequencies.

It will also not allow airlines to launch new flights to Shenzhen International Airport except for China Southern Airlines, Hainan Airlines and Shenzhen Airlines that have bases there because the airport is already operating beyond its capacity.

The Chinese aviation industry is facing increasing pressure to improve airlines' punctuality amid a tight supply of landing slots and surging demand for air travel.

"The policy of halting new flights is positive for China's three biggest airlines, China Southern, China Eastern Airlines and Air China, which separately dominates the air travel market in Guangzhou, Shanghai and Beijing," said Li Shurong, an analyst at a Chinese private-equity fund.