Tensions with Thailand and Cambodia remain elevated, with the Southeast Asian neighbors announcing tit-for-tat measures that are stoking nationalist fervor on both sides and stymieing bilateral trade, including a suspension by Phnom Penh of all Thai fuel and gas imports that came into effect on Monday.

In Bangkok, days after the parliamentary majority of the ruling coalition led by Paetongtarn's Pheu Thai party was threatened by the exit of a major alliance member, Deputy Prime Minister Phumtham Wechayachai sought to project unity.

"I'm 100% confident that we will move ahead strongly after the cabinet reshuffle is completed this week," he told reporters.

"You will see a new way of working that's different from before."

Paetongtarn, a 38-year-old political novice and daughter of divisive former Prime Minister Thaksin Shinawatra, has come under fire after a phone call between her and former Cambodian leader Hun Sen to diffuse a long-festering border dispute became public last Wednesday.

In the audio, which was released in full by Hun Sen after the initial leak of a clip, the Thai premier appears to grovel before the Cambodian politician and also denigrates a senior Thai military commander in charge of the disputed border area.

Hours after the audio became public, the second-largest coalition member, the Bhumjaithai Party, quit the government, putting its parliamentary majority and Paetongtarn's premiership under threat.

Pheu Thai has managed to hold the remainder of its coalition together, with the cabinet reshuffle meant to redistribute ministerial positions previously held by Bhumjaithai.

The coalition's stability will be tested in parliament, which reconvenes next week, and on the streets as anti-government groups plan a major protest to call for the prime minister's resignation which will start on Saturday.

Adding to the pressure, Paetongtarn also faces scrutiny from the judiciary after a group of senators seeking her removal petitioned the Constitutional Court and an anti-graft body to investigate her conduct over the leaked phone call.

"The government cannot take anything for granted," said Titipol Phakdeewanich, a political science professor at Ubon Ratchathani University.

"There's more instability ahead."

At the root of the current crisis for Paetongtarn and Pheu Thai is a historic border dispute with Cambodia, which has previously led to violent clashes, including the death of a Cambodian soldier during a skirmish last month.

Partly banking on strong ties between the Shinawatra family and Hun Sen, the government initially pushed for a diplomatic solution to the flare-up, even as Cambodia moved to petition the International Court of Justice to resolve the matter.

However, the unexpected release of the audio not only brought the Thai government to the brink, it has also led to a further deterioration in relations between the neighbors.

Hun Manet, Cambodia's prime minister and Hun Sen's son, said on Sunday that his administration would stop all fuel and gas imports from Thailand, following an earlier move to stall the entry of some Thai agricultural produce.

"Fuel supply companies in Cambodia are able to import sufficiently from other sources to meet domestic fuel and gas demands," he said in a post on Facebook.

For its part, the Thai government has handed over control of border crossings along the Cambodian frontier to its military, which has tightened entry restrictions and shut down one crossing point, citing security concerns.

Cambodia was Thailand's 11th largest export market last year, with $10.4 billion in bilateral trade between the neighbors, dominated by precious stones, jewelry and fuels, according to Thai government data.

And more than half a million Cambodian workers are employed in Thailand, according to the Thai Labour Ministry.

"The Cambodia situation is complex; it isn't about just a conflict between the two countries," said Titipol, "There is also a Hun-Shinawatra dimension that could still shake the government."