The Mekong River's flow dropped to the lowest levels in more than six decades from 2019 to 2021, according to the inter-governmental Mekong River Commission (MRC), impacting agriculture, fishery and livelihoods for more than 60 million people in Laos, Thailand, Cambodia and Vietnam.

A new joint study released on Monday between the MRC and the China-founded Lacang Mekong Water Resources Cooperation Center (LMC Water Center) attributed natural factors such as rainfall patterns, evaporation rates and topography for the decline, but also cited human activities such as infrastructure development and water management as contributing to the dry conditions of the river.

The study recommended "real-time sharing of storage levels and hydropower operations" and enhanced notifications of sudden changes in the way water storage operates among Mekong countries, including China, which is crucial in improving management of the 4,350-km (2,700-mile) long river.

China, which operates 11 out of 13 hydropower dams on the Mekong River has disputed previous accusations that it was holding back water upstream during drought periods. Beijing in 2020 pledged to share some water data with Mekong countries.

Authorities in Thailand, Laos, Cambodia, Vietnam and China did not immediately respond to requests for comment on the findings of the joint study.

(Reporting by Panu Wongcha-um in Bangkok, additional reporting by Beijing Bureau, Khan Vu in Hanoi and Prak Chan Thul in Phnom penh; Editing by Sharon Singleton)