The latest border dispute involved an armed confrontation May 28 in a relatively small contested territory in which one Cambodian soldier was killed.

Thailand's Prime Minister Paetongtarn Shinawatra has visited the border with Cambodia as she faced resignation calls following a leaked phone call between her and Cambodia's former leader discussing recent border tensions.

Thailand's Ministry of Foreign Affairs announced Thursday that it will hand a letter of protest to Cambodia's government after a call between the two countries was allegedly leaked by a high-profile Cambodian official.