China allegedly supplied Cambodia with weapons to that were used in clashes with neighbouring country and CCP ally Thailand.

The seemingly double-dealing Asian superpower, which also supplies arms to Thailand, was said to have flown munitions into Sihanoukville weeks before violence erupted along the border in late July.

The New York Times, citing Thai intelligence documents, reported that Chinese Y-20 cargo jets delivered some 42 containers to the coastal Cambodian city over the three days.

The military hardware - including Soviet-era BM-21 rocket launchers, self-propelled howitzers, and other ordnance - were allegedly stored at the Ream Naval Base before being moved to the frontier.

Experts said Cambodia had been fortifying its forces along the border allegedly to take a 'more provocative posture' toward Thailand.

Nathan Ruser, an analyst for the Australian Strategic Policy Institute, told the New York Times: 'The entirety of the evidence suggests that there has been a concerted decision by the Cambodian leadership in the months and years leading up to the border clashes to change the status quo along the border.'

In a statement on October 2, the Chinese Embassy in Thailand denied the reports, claiming the Chinese-made artillery came from previous 'cooperation projects'.

It said: 'China reiterates that since the outbreak of the border conflict between Thailand and Cambodia, as a friendly neighbor to both countries, China has been making positive efforts in its own way to help de-escalating the situation. China has not provided Cambodia with any military equipment for use against Thailand. The military equipment Cambodia possessed from China comes from existing cooperation programs.

'China has no selfish interests in the border conflict between Thailand and Cambodia. China supports ASEAN's effort to promote political settlement in the 'ASEAN Way' and is willing to maintain close communication with regional countries including Thailand, Cambodia and Malaysia, to play a constructive role for consolidating a sustainable ceasefire and restoring peace and stability along the border.

'We urge all parties concerned to focus on promoting peace, stability of the region and the well-being of the people, by taking positive and constructive actions to de-escalate the situation, rather than maliciously spreading false information or rumors to stir up trouble.'

Thailand and Cambodia have been fighting for more than a century over several undemarcated sections of their 817-kilometre (508-mile) border, which was originally mapped by France in 1907 while Cambodia was still its protectorate.

But tensions flared in the long-disputed frontier as both accused each other of instigating violence on July 24, which killed at least 48 and temporarily displaced some 300,000 on both sides of the border.

Cambodia claimed responsibility for the alleged war crime of firing rockets into Thailand that struck a gas station, killing a number of children.

The two nations have reached a shaky truce following talks facilitated by Malaysian Prime Minister Anwar Ibrahim, chair of the Association of Southeast Asian Nations (ASEAN).