The signing last week of a military aid pact between China and Cambodia is not good news for the region. The deal was signed in Phnom Penh, during a visit by Gen Qi Jianguo, deputy chief of staff of the Chinese army. The agreement commits China to train the Cambodian army, and to start an upgrade of the country's military hardware. The first shipment of 12 helicopters is to begin immediately.
Cambodia and China publicised the military training pact and therefore cannot be accused of secrecy. The Phnom Penh government of Prime Minister Hun Sen has been openly appealing for military aid for almost three years. Washington, for example, bans military hardware sales because of the Hun Sen government's disdain for human rights.
The timing could not be worse for China to step into the twin roles of military adviser and arms supplier to Cambodia. There is strong concern over Chinese actions in the region. Many, including the governments of the Philippines and Vietnam, fear China is moving far too aggressively. At the same time, Hun Sen and his government are seen as yielding too much, too fast to Beijing's campaign to insinuate itself in the Asean region.
Beijing's attitude on disputes over the South China Sea is frequently truculent, always troubling. At two summits in a row, then-Asean chairman Cambodia served as China's proxy in stonewalling attempts by members to begin peaceful talks. The breathtaking claims by Beijing that it owns the South China Sea and all islands and shoals have been backed by belligerent gunboat diplomacy.
Vietnam, the Philippines and most Asean members are deeply troubled by China's refusal to discuss territorial disputes. Thailand, which has no such conflicts with China, announced last week it will promote diplomacy. Foreign Ministry permanent secretary Sihasak Phuangketkaew hopes to arrange substantive discussions between China and the Philippines. Manila has begun steps to ask the United Nations to censure China over dangerous conditions in and around the Spratly Islands.
China's massive economic "investment" in the region is also an issue. There is little doubt that in Cambodia, Myanmar and elsewhere, China is exerting financial pressure to further its military and diplomatic goals.
This directly concerns Thailand. Ultra-nationalists want the government to bypass talks with Cambodia, and confront its neighbour over the Preah Vihear temple land dispute.
Army chief Prayuth Chan-ocha even said last week that war is an option, although he called it "the last resort". Nor is the testy war of words between Hun Sen and opposition leader Abhisit Vejjajiva helpful to peaceful diplomacy.
In addition to its military training and aid, China agreed last week to build a 404km railway from Preah Vihear to Koh Kong. This would run virtually parallel to almost all the Thai-Cambodian frontier.
The deal to build up the Cambodian army and air power puts both China and Cambodia in a difficult position with the region.
It comes just when testiness is once again growing over the land around the temple.
One hopes Cambodia will understand its China deal over military aid has raised the concerns of its neighbours. Phnom Penh should take steps to explain and reduce the tension.