Since the inauguration of the Belt and Road Initiative (BRI) in 2013, Cambodia-China relations have improved significantly, mainly due to the increasing Chinese investment and projects in Cambodia. Simultaneously, the relationship between the US and Cambodia has severely deteriorated.
The Chinese government and some major Chinese companies are known to be involved with key infrastructure projects in Cambodia, including the Dara Sakor tourism resort, Ream Naval Base, Phnom Penh-Sihanoukville Expressway and the Funan Techo Canal.
Some of these projects raised significant suspicion and concerns about increased Chinese influence in the region — in particular from the US, which expressed defence concerns that China may use some of those facilities for military purposes.
In full: https://www.thinkchina.sg/politics/how-japan-and-south-korea-can-revitalise-cambodia-us-relations
