China plans to invest $636 billion through 2020 in water-related projects, a government official said.

Speaking at the Sixth World Water Forum in Marseille, France, Chinese Minister of Water Resources Chen Lei said no other country faces as many water challenges as China.

For China's population of 1.3 billion, pressing water issues include poor access to water, pollution, uneven distribution and frequent natural disasters such as floods and droughts.

While the government will provide most of the financing, some projects would be open to foreign investors, Chen said in a China Daily newspaper report.

Projects would be geared toward treating heavily polluted rivers and lakes and to improve the water ecosystems in ecologically fragile areas.

Data from the ministry indicate that in 2010, 40 percent of Chinese rivers were seriously polluted and unfit for drinking after 75 billion tons of sewage and waste water were discharged.

Chen also said the government would push forward with construction of rural water supply projects for completion by 2015.

About two-thirds of Chinese cities are short of water and nearly 300 million rural dwellers have no access to safe drinking water.

"Water issues bear on the survival and development of human beings and the well-being of people of all countries," Chen said Wednesday in an interview with Chinese state-run news agency Xinhua on the sidelines of the forum.

"(China) is willing and ready, with countries and regions, to work out sound solutions for water, promote in-depth exchange and cooperation, share successful experience(s), work out sound solutions, address challenges hand in hand, and to support sustainable development of economy and society with sustainable utilization of water resources," he said.

At the forum Tuesday, China, Japan and South Korea signed an agreement aimed at strengthening coordination among the countries in managing water resources and dealing with water-related disasters.

Chen said the agreement will "unfold a new chapter for the cooperation among the three countries in the water sector."

On Wednesday, China and the European Union signed a joint statement to boost water cooperation.

Initiatives under the China-Europe Water Platform may include policy dialogue, joint research and projects, with funding provided by both sides, the statement says. Participants may include government agencies, river basin authorities, research institutes, non-governmental organizations and the private sector.

Some 140 ministerial delegations are attending the forum, which takes place every three years. The current series of meetings continues through Saturday. China joined the World Water Council, organizer of the forum, in 2009.