Torrential rains battering south and central China have left 175 people dead and forced the evacuation of 1.7 million, as washed out roads and railways hampered rescue work Monday.

Premier Wen Jiabao called for greater efforts to battle flooding that has also left 107 people missing since June 13, as more rains are forecast in the next few days, the government said.

"In the coming days another round of heavy rain will hit areas in the south. We are facing a bigger test, so we need to make better preparations to avoid disaster," Wen said on state television.

"We are in a crucial period. We must be fully prepared and step up organisation of disaster response work," he said on a visit to the water-logged region of Guangxi.

The torrential rains and flooding have affected over 25 million people and caused 29.6 billion yuan (4.3 billion dollars) in estimated economic losses, the Civil Affairs Ministry said.

The ministry's latest death toll was up from the 147 dead and 93 missing reported on Sunday.

The water levels of at least 35 rivers, mostly in Fujian, Jiangxi and Hunan provinces, have exceeded warning marks and are threatening surrounding cities and farmlands, it said.

Landslides were wreaking havoc in mountainous areas throughout the region.

Soldiers and armed police have been sent to the hardest hit areas to help the rescue effort.

With roads and bridges washed out, the government dispatched hundreds of rescue boats to inundated areas in an effort to evacuate thousands stranded by the flooding.

Eleven major state highways, most leading into Fujian province on the nation's southeastern coast, have been blocked by flooding or landslides, China National Radio reported.

Besides clearing roads, workers are also scrambling to restore electrical power to many of the hardest hit areas that were left without electricity over the weekend.

A total of 393,000 homes have been damaged, 144,000 houses have collapsed and nearly 1.36 million hectares (3.3 million acres) of crops have been affected, the government said.

Torrential rains continued to fall on the hard-hit regions of Fujian, Zhejiang, Jiangxi and Guangxi on Monday, with downpours expected to continue over the next 10 days, the National Meteorological Centre said.

The weather bureau has said that some of the rainfall in the south was up to three times greater than normal years.

Photos issued by the state media showed washed out roads and people wading through waist-high water.

The unrelenting rainfall has also disrupted dozens of train services to the affected regions, including some services from Beijing and Shanghai, leaving thousands of passengers stranded, media reports said.