Foreign Minister Wang Yi has begun a two-day visit to Cambodia, a trip analysts say is intended to bolster a key Beijing ally in Southeast Asia amid Washington's growing interest in the region.
Wang will meet Cambodian Prime Minister Hun Sen and hold talks with his Cambodian counterpart, Hor Namhong. The trip comes just days after Beijing announced its latest US$14 million gift to the country - four container scanners to use at border checkpoints.
Cambodia has long been one of China's most important allies in the region, receiving nearly US$3 billion in development aid from Beijing over the past two decades. The relationship has taken on new significance in light of increased involvement in Southeast Asia by the US and other Western nations.
Phnom Penh has provided key support to Beijing in its territorial disputes in the South China Sea. But analysts say the allies must be careful not to repeat the experience of Myanmar, where the public has grown suspicious of Beijing's intentions.
"In fact, the relationship between China and Cambodia is so close that there are concerns over [the] influence that China has over Cambodia," said Heng Pheakdey, founding director of the Enrich Institute for Sustainable Development. "China's money does come with some string[s] attached in [the] form of business and political favours.
"While Cambodia needs China's money for economic growth, China needs Cambodia for strategic and political reasons," said Heng Pheakdey, who has written extensively on Sino-Cambodian relations.
China also remains Cambodia's largest foreign investor and a vital trading partner. Chinese companies are active in infrastructure, resource extraction and energy generation, despite charges of unfair and unsustainable practises by human rights and environmental activists.
In December, Cambodian Petrochemical Company and China Perfect Machinery Industry jointly announced the construction of Cambodia's first oil refinery, which is expected to be completed by 2015.
Heng Pheakdey said many of China's investment projects - particularly those in the energy and natural resource sectors - have often been associated with poor quality and a lack of consideration for social and environmental impacts.
China's challenge was thus to rebuild its image as a good partner by promoting sustainable development.
"China needs to focus more on quality rather than quantity," Heng Pheakdey said.
Bernt Berger, head of the Asia programme at the Institute for Security and Development Policy, said the visit was not likely to lead to many new developments. But he said the relationship between Beijing and Phnom Penh was strong and at less risk of being weakened by increased US involvement, compared with countries like Myanmar.
"Beijing does them favours, and they do favours back," Berger said.