A new Cambodian infantry brigade undertook live-fire weapons training just south of the border with Laos yesterday, six months after Prime Minister Hun Sen dispatched troops to the border amid tensions.

Infantry Brigade 128, created last August shortly after border friction with Laos, used live mortars in a training designed to improve skills and to “get to know the location in order to defend our country and our territorial integrity”, said Defence Ministry spokesman Chhum Socheat.

“We also informed the Laos side before the live ammunition exercise,” he said. “We have solidarity with each other . . . and we have never had any problems.”

However, last February Laotian troops crossed the Sekong River to prevent Cambodian military engineers from building a road. In August, Hun Sen sent troops to the border and gave Laos an ultimatum to withdraw their men within six days or risk consequences.

Yesterday’s exercises took place in a contested area, known as O’Alay, in Stung Treng.

Paul Chambers, of Naresuan University in Thailand, said the mortar exercises were no doubt about “getting Cambodians to rally around the flag and the [ruling Cambodian People’s Party] as the general election in Cambodia approaches”.

“The border dispute with Laos is puny compared to that with Thailand and Vietnam. However, the fact that Laos has the smallest army in Southeast Asia makes it smart politics to use Laos as the convenient punching bag with the least likely consequences for Hun Sen.”

Additional reporting by Erin Handley