This is the shocking moment an angry Thai tourist punched a Cambodian soldier at an ancient Khmer temple amid a bitter border dispute.

The suspect, Sommai Srisukranan, reportedly struck the Cambodian troop twice before fleeing from the Prasat Ta Muean Thom temple in Surin on Sunday.

Footage shows Sommai, an ex ranger who now heads a volunteer rangers club, taking the Cambodian officer's hand and shaking it in an apparently friendly gesture. However, he suddenly threw a jab at the man, then spun around to bolt from the scene.

Thai military officers spoke with the assaulted soldier to de-escalate tensions before later arresting Sommai - one of many Thais whipped up into a nationalistic fervor over the border dispute with their neighbour.

Major General Winthai Suvaree, spokesman for the Royal Thai Army, said the altercation was reported at 10:20 am.

He said: 'The Thai tourist physically assaulted a Cambodian soldier at the Ta Muean Thom temple. He hit him from behind and in the face before fleeing.

'We later identified him as Mr. Sommai Srisukranan, a former volunteer ranger and current president of both the Pak Thong Chai Volunteer Ranger Club and the Samut Sakhon War Veterans Network.

'Since the location is a shared tourist site, our army officers worked to reach an understanding with the Cambodian side to avoid further diplomatic tensions.'

Sommai claimed the Cambodian soldier was biased for refusing to reprimand a Cambodian tourist who had been taunting him.

He was detained and handed over to the police for legal proceedings.

The alleged attack occurred just a week after Thai and Cambodian tourists clashed at another Khmer temple along the border.

The row was reportedly sparked by a Cambodian woman posing for photos holding a blue checkered scarf embroidered with the Cambodian flag.

The nationalistic display angered several Thai tourists, who allegedly threatened to use violence and blocked the woman from taking photos of the sacred ruins, which date back to the mighty Khmer Empire before it was absorbed into Siam.

Ten Cambodian troops assigned at the temple later stepped in to defuse the tensions, with both sides dispersing after mediation.

Tensions between Thailand and Cambodia escalated after a clash between troops from both countries in a disputed area in Nam Yuen district, Ubon Ratchathani, on May 28, resulting in the death of a Cambodian sergeant.

Thailand expressed its intention to resolve the dispute through existing bilateral mechanisms.

However, Cambodia vowed to take the case before the International Court of Justice in The Hague.

Former Cambodian Prime Minister Hun Sen and current Prime Minister Hun Manet claimed that the disputed area belongs to Cambodia.

While Thailand maintains that the area is a no-man's land within an un-demarcated zone.