Thailand's military has closed border crossings into Cambodia to almost all travellers, including tourists and traders, citing security concerns as tensions between the two Southeast Asian neighbours remain escalated over a simmering border dispute.

Thailand and Cambodia shut several border crossings in tit-for-tat moves, ratcheting up tensions between the two Southeast Asian neighbors as Prime Minister Paetongtarn Shinawatra fights to save her government from a political crisis triggered by a leaked phone call over the weekslong standoff.

Dozens of tourists and workers, some carrying children, were left stranded on Tuesday at Thailand's main land crossing with Cambodia, after the army stopped almost all border traffic in an