More than 80,000 people have been evacuated because of heavy rains and floods in the southwestern Chinese province of Sichuan, state media reported on Monday.

Water levels at major rivers in the province were above warning levels following heavy rainfall from Friday to Sunday. One reservoir in the city of Dazhou exceeded its flood limit by 2.2 metres, according to the official China News Service.

It said more than 440,000 people have now been affected by floods in six cities across the province.

State broadcaster CCTV said on Saturday that heavy rain had already caused 250 million yuan ($38.57 million) in economic losses in Sichuan, with 45 houses destroyed and 118 severely damaged.

China is routinely hit by heavy rainfall during the summer, but experts have warned it must now improve the resilience of its cities as extreme weather becomes more frequent.

Chinese weather officials told reporters last week that rising temperatures had increased the likelihood of heavy rainfall across the globe, and the impact in China was likely to get worse in coming years.

"Extreme events such as high temperatures and heavy rainfall have increased and the level of climate risk in China is on the rise," said Chao Qingchen, vice-director of the National Climate Centre, a state think tank.

She said higher temperatures and rainfall were making China's water resources more vulnerable, and warned that extreme weather was also posing a bigger threat to economic development.

Last month, the central Chinese province of Henan suffered its worst rainstorms in recorded history, with 19 state weather monitoring stations registering the highest daily rainfall ever.

The floods killed more than 300 people, mostly in the provincial capital of Zhengzhou, which saw almost a year's worth of rainfall in just a single day, China's weather bureau said.