Failing Cambodian casinos are scrambling to lure back Thai tourists whose numbers dwindled amid a bitter border conflict.

Casino owners in Poipet launched various promotions as their revenues declined from reduced Thai clientele during the border spat.

With gambling in Thailand banned, the venues are the nearest legal options for residents.

But the Thai army had banned Thais - both tourists and workers - from crossing the border in Sa Kaeo on Tuesday, June 17 'for their own safety'.

In response, the gambling houses offered hotel discounts, and partnered with airlines to provide direct flights and shuttle services from major Thai cities, in a desperate bid to keep their businesses afloat after a drastic 90 per cent drop in the number of Thai customers.

Nart, 34, a Thai employee at a casino in Poipet, said: 'Some casinos stayed open even after nearly all Thai employees had left. They were dealing with problems like unstable electricity and internet.

'Most of the customers were Chinese and other foreigners, though a few Thai gamblers were still there who likely had flown into Cambodia. Most of those still in Poipet arrived before the checkpoint closed. The situation isn't frightening, but with so few Thai nationals left, I hope the checkpoint reopens soon.'

Tensions between Thailand and Cambodia have intensified following a deadly clash between their troops in a disputed area of Ubon Ratchathani, on May 28.

The skirmish killed a Cambodian sergeant. Thailand said it was committed to resolving the dispute conflict through bilateral means, while Cambodia has vowed to bring the case before the International Court of Justice in The Hague.

Furious Thai locals have slammed Prime Minister Paetongtarn Shinawatra, daughter of former Man City owner Thaksin, over a leaked phone call with Cambodian ex-dictator Hun Sen in which she allegedly blamed a rogue Thai general for the border conflict.

The Thai leader has since apologised for the conversation, which has caused her ruling coalition to collapse as a major allied party withdrew from their alliance.

Thailand and Cambodia have a fractious history. The Khmer Empire once stretched across much of Southeast Asia before the ancient leaders moved their base south to Phnom Penh in the 16th century amid water shortages.

Thai tribes used it as a chance to encroach and claim much of the deserted land, including priceless sandstone temples and artefacts.

In the 1970s, Thailand supported the Khmer Rouge while they carried out one of the world's worst ever genocides. The country then provided sanctuary for the group's murderous leaders, even allegedly stealing aid funds that were intended to rebuild Cambodia.