Intermittent military clashes between Cambodia and neighbouring Thailand, host of the SEA Games beginning on Dec 9, have erupted since earlier this year.

More than 40 people were killed during five days of combat in July.

While a truce backed by US President Donald Trump has halted most hostilities, diplomatic tensions remain.

In a letter dated Wednesday, the National Olympic Committee of Cambodia (NOCC) informed the Southeast Asian Games Federation that it would not participate in sports including football, petanque, wrestling, judo and karate at the regional Games next month.

“This adjustment has been made due to significant security concerns, which poses challenges to ensuring the safety and protection of our athletes and officials,” the letter says.

NOCC secretary-general Vath Chamroeun told AFP that the decision was “about safety”, declining to say whether it was related to the border dispute.

“The reduction of the number of athletes means it is easy for us to control,” he added.

In a Facebook post, the NOCC said Cambodia would now send 150 athletes to compete in 13 sporting events, down from 333 athletes earlier announced.

The dispute between Thailand and Cambodia centres on a century-old disagreement over borders mapped during France’s colonial rule in the region, with both sides claiming a smattering of boundary temples.