The inter-governmental Mekong River Commission (MRC) said on Monday that levels on the vital waterway have "slightly" increased and it would look into why its outflow data from Chinese dams upstream differed from data later given by Beijing.
Whether or not China's 11 dams are harming downstream nations dependant on the 4,350 km (2,700 mile) river has become a geopolitical issue, with the United States urging Lower Mekong governments to demand answers.
China says there are many reasons for falling river levels in recent years, including low rainfall and dams on other tributaries.
The river in Laos, Thailand, Vietnam and Cambodia had fallen in many parts since January, with some sections turning blue instead of the usual brown colour - signaling shallow water and low levels of nutrition-rich sediment in the river that nearly 70 million people rely on for livelihoods.
The MRC said outflow from southern China to mainland Southeast Asia had increased from 768 cubic metres per second earlier this month to 1,020 cubic metres per second on Monday.
China's Ministry of Water Resources said outflow at Jinghong, the closest dam to mainland Southeast Asia, had been consistently over 1,000 cubic metres per second since end of January, the MRC said.
China agreed last October to share water levels data with the MRC.
The commission earlier had attributed the dry condition partially to outflow restriction from upstream Chinese dams, a finding that the Chinese government disputed. It gave higher numbers for downstream water levels than the MRC data.
"This discrepancy between outflow estimates may be due to the use of different methods to calculate discharges," the MRC statement said.
The MRC said its experts and those of China were "working together to provide more consistent water discharge information".
Chinese authorities did not immediately respond to a request for comment.
In January, Beijing notified its neighbours almost a week after it held back water at a hydropower dam.
(Reporting by Panu Wongcha-um; Editing by Martin Petty)
