China and Mekong regionalism: A reappraisal of the formation of Lancang‐Mekong Cooperation

Abstract The Mekong region is witnessing a regional order reconfiguration triggered by the China‐led Lancang‐Mekong Cooperation (LMC). Little research is available regarding the history of this sub‐regional grouping, particularly about its formation. Using sources from a recently opened archive in Bangkok, this article reappraises the origins and evolution of the initiative within the lens of regional group formation theory. Findings show that LMC is a revised version of Thailand's proposal for the formation of a dialogue on the management of the Mekong River that was initially dismissed by China. As China under Xi Jinping‐era claimed great power status with a droit de regard over the near abroad, it has used the LMC to exercise exclusive leadership over the Mekong region. This can be seen in the preparation of institutional infrastructure for the construction of a China‐Indochina Peninsula Economic Corridor (CICPEC) as part of China's wider Belt and Road Initiative (BRI) strategy.