In the latest flare up in tensions between the two countries, Lao authorities temporarily shut a border crossing with Cambodia and dispatched more troops to an undemarcated area on the northern border after Cambodian authorities began renovating an old French border outpost.

According to local officials, Laos shut the Voen Kham border crossing in Stung Treng province’s O’Svay commune on Sunday and briefly again yesterday until authorities from Thala Barivat district scrambled to find a resolution.

O’Svay commune police chief Ham Sovorn said Laos closed the checkpoint after border police tried to upgrade a colonial-era border outpost located in an un-demarcated “white zone” next to the Mekong River in the commune’s Deum Lvea area. Armed Lao troops then moved into the white zone and demanded Cambodian authorities halt the construction, which they did.

Sovorn said relations with their counterparts across the border had been tense since the beginning of March, as the Lao military continued construction of an outpost in a similar white zone bordering Samaki commune. Work on that Lao outpost provoked a diplomatic protest by provincial authorities last April but Sovorn said work had progressed nonetheless.

“We do not allow them to build their border post in Dong Kralor Chas [the area of the planned Lao outpost], but they still want to build it without informing us, and already made a well,” he said. “But when we built our post along the river, they stopped us and sent three trucks full of forces . . . They were all equipped with guns and they have prepared for any irregular situation . . . They are ready to attack us.”

Reached yesterday, Thala Barivat district police chief Sem Sitha said Laos had stationed more troops near O’Svay commune. He said the border had been opened and closed a few times since the stand-off began.

“But when leaders had talked with them, they have reopened it,” he added. Thala Barivat District Governor Thorng Srean said the border was now open and the situation was calm, but declined to give further details calling it a “national affair”.

A border policeman, who requested anonymity, said border police planned to renovate the colonial checkpoint as a response to Laos’s attempts to build a military outpost.

“The demarcation [in that area] has not been agreed on by both governments but the Laotians try to build [their base] . . . Therefore we want to renovate the old post in the Deum Lvea location, but they brought their forces in and shut the border,” he said.

The incident follows another flare-up in February in Stung Treng’s Siem Pang district, where some 400 Lao troops entered a white zone to stop Cambodian military engineers from building a road on what they maintained was the Kingdom’s territory.

Provincial authorities were unreachable yesterday. Defence Ministry spokesman Chhum Socheat, meanwhile, said he was “busy” before hanging up.