The leaders of Cambodia, Vietnam, Myanmar, Thailand and Laos, along with Chinese Premier Li Keqiang, announced the adoption of a five-year plan for cooperation on matters relating to the Mekong River, though experts and observers yesterday questioned who would benefit from China’s increasing involvement in the management of the vital waterway.

The announcement was made at the Peace Palace in Phnom Penh yesterday, where leaders gathered for the Second Mekong-Lancang Cooperation (MLC) leaders meeting. After a day of closed-door meetings, the leaders of the six countries gave a 19-minute press conference at which it was announced that the Phnom Penh declaration had been signed, and the five-year plan adopted.

While reporters were provided with the text of the six-page declaration, which outlined in broad terms areas of cooperation, the contents of the five-year plan remained undisclosed.

Speaking briefly at the press conference, Prime Minister Hun Sen thanked China – the Kingdom’s largest donor and an increasingly lonely ally as Cambodia pivots away from the West – for its “unwavering support of Cambodia’s co-chairmanship” of the cooperation body. Cambodia handed off the temporary co-chairmanship to Laos yesterday. China is the other, permanent co-chair.

Keqiang yesterday enumerated a laundry list of ways China’s presence benefited the five other Mekong countries, but China’s regional leadership took centre stage in his remarks. “This institution was made by China,” he said, noting that when it came to fulfilling the MLC’s objectives of peace, stability and prosperity, “China takes on this responsibility”.“China needs a stable environment in its neighbourhood,” he added.

The Phnom Penh declaration made promises of peace, stability, connectivity, development and, notably, noninterference.

The Mekong River supports the livelihood of millions, and is a pressing food security and ecological concern for downstream countries such as Cambodia, and yesterday’s declaration promised cooperation in those fields, as well as in “green and sustainable development” through the creation of an unspecified “plan”.

But Paul Chambers, a Southeast Asia expert at Thailand’s Naresuan University, was doubtful. “There is no evidence that MLC would seriously address such issues: that is not the purpose of the MLC,” he wrote in an email, noting that “human security issues are under the purview of the Mekong River Commission [MRC], a body which China has refused to join to prevent MRC jurisdiction over China”.

Chambers went on to characterise the MLC as more of an aid cash-grab for Mekong countries. “China and these countries are only thinking in the short term,” he said. “The meeting is meant to shore up mainland Southeast Asian support for Chinese dams, trade corridors, and transportation linkages which facilitate expanded Chinese penetration into the Mekong Region.”

The MRC – to which Myanmar and China are not parties, despite having been invited – has long been the main institution attempting to ensure the sustainable management of the Mekong, providing invaluable environmental, economic and social data to guide development decisions.

In emailed comments MRC CEO Dr Pham Tuan Phan noted that despite the MRC not being invited to the MLC meeting, an invitation would be extended to the MLC for the MRC’s upcoming summit in April.

Phan re-iterated the MRC’s position that the MLC was a complement, not a replacement, to its own activities, and noted that calls for Myanmar and China to join the MRC continue.

But China’s reluctance to work more closely with the MRC was one of the main hindrances to efforts to effectively preserve and manage the waterway, according to Maureen Harris, of the NGO International Rivers.

“China’s lack of full participation in the MRC – which includes the four lower Mekong countries as members – has prevented the MRC from addressing the downstream impacts of Lancang dams,” she wrote in emailed comments, referring to dams on the Mekong in China, which effectively place the regional power’s hand on the tap for countries downstream.

Chinese corporations have also been behind hydropower dams in the Lower Mekong Basin that experts say have the potential to disrupt the livelihoods and food security of millions of residents.

The MLC’s mandate is “much broader” than water governance, and this may mean the institution may have “greater influence” on issues that relate to hydropower and other infrastructure projects that impact the river. However, unlike the Mekong River Commission, it has no “mechanism for cooperation, consultation and agreement”.