MARIMI KISHIMOTO, Nikkei staff writer

BANGKOK — The U.S. and China are locking horns over the management of data on the Mekong River, the longest watercourse in Southeast Asia, which feeds millions of people living in its basin.

The Mekong originates in southern China and courses over 4,000 km through Myanmar, Thailand, Laos, Cambodia and Vietnam before emptying into the South China Sea.

China recently announced a plan to create a system for sharing water management data on the river with its Southeast Asian neighbors by the end of the year, which has irked the U.S.

On Aug. 24, Premier Li Keqiang spoke at a videoconference for the summit meeting of the Lancang Mekong Cooperation organization — grouping the six nations of China, Laos, Myanmar, Thailand, Cambodia and Vietnam — and unveiled a plan to establish a platform for sharing annual data in order to deal with floods and droughts.

Details were not disclosed, but it is believed that the platform will be designed to allow the countries to share information such as precipitation amounts and water levels.

It was the third summit of the LMC, which was launched in 2015.

Li stressed the importance of expanding and upgrading cooperation among the six nations, saying, “Drinking water from the same river, we, the LMC countries, are as close as one family living in a community with a shared future.” He added, ” We need to take our cooperation in water resources to a new high.”

Traditionally, China has published water management data concerning its upper portion of the river only during the flooding season from June through October.

Beijing apparently changed this policy following a record drought in 2019, which damaged crops in Thailand and Vietnam, two leading rice exporters, triggering a surge in international rice prices.

But a report published by a U.S. think tank has accused China’s dams on the upper stretches of the river of causing water levels to decline. China called this “groundless” and blamed the weather for the drought.

Thitinan Pongsudhirak, an associate professor at Thailand’s Chulalongkorn University who is an expert on security issues, said, “By offering to share hydrological data, Premier Li is stamping and cementing China’s position and upstream leverage.”

Beijing has already been providing massive funding for infrastructure development in the basin countries for years under its Belt and Road Initiative.

Washington meanwhile is poised to create a new framework for cooperation with countries along the Mekong as a step to prevent China from expanding its influence.

U.S. Secretary of State Mike Pompeo will take part in a series of virtual meetings with his counterparts from the Association of Southeast Asian Nations and other countries in the Indo-Pacific region from Wednesday through Friday.

On Friday, he will co-chair the inaugural Mekong-U.S. Partnership ministerial meeting, launching the new framework for cooperation with the foreign ministers of Cambodia, Laos, Myanmar, Thailand and Vietnam plus the ASEAN secretary-general.

The new partnership will expand on cooperation that started in 2009 under the Lower Mekong Initiative, according to the U.S. State Department.

Washington’s new Mekong move is clearly a response to Beijing’s efforts to pull the basin further into its diplomatic orbit.

China’s move has provoked a backlash from the Mekong River Commission, a framework for multilateral cooperation over the waterway that has been supported by the U.S. and Japan.

On the day following Li’s speech, the MRC Secretariat issued a statement welcoming Li’s proposal but calling for harnessing the MRC’s “existing, long established platform.”

The MRC was launched in 1995 by four of the five basin countries, excepting Myanmar. While its members mostly overlap those of the China-led LMC, the MRC boasts a longer history of effective development and cooperation, funded by Japan and others.

With the help of the U.S., the MRC has been operating a system to share water data to help forecast floods and droughts.

An Pich Hatda, the MRC Secretariat’s chief executive officer, said: “What is missing is the same level of data and information from the upper Mekong River basin.” The MRC has effectively called on China to provide information to improve and upgrade the MRC’s existing platform instead of creating a new one.

As the U.S. and China compete for influence in the South China Sea, the Mekong River — a cornucopia of resources for the entire region — is becoming one of the many issues that the U.S. and China disagree on.