Prime Minister Hun Sen (right) hugs his Vietnamese counterpart Nguyen Tan Dung during the inauguration ceremony of the last border post at the terminus of the land boundary between Cambodia’s Kampot province and Vietnam’s Kien Giang province in June. Photograph: Heng Chivoan/Phnom Penh Post

Prime Minister Hun Sen vowed yesterday to set the record straight on the demarcation of the Vietnam border, an issue that flared in June when the government announced it would cede two villages to Vietnam.

Hun Sen spent much of his speech to 2,500 university graduates at the National Institute of Education mocking the “storm-in-a-clay-pot” Democratic Movement for National Rescue (DMNR) and taking aim at the Sam Rainsy Party.

But his announcement that he had accepted the SRP’s invitation to address the National Assembly about the border issues – something he will do over the course of four hours – was exactly what the opposition wanted to hear.

“I will go to answer questions. I have sent my letter to the National Assembly, but I am still waiting for their response,” he said, adding that border issue “must be clear”.

Despite his commitment, the prime minister objected to opposition leader Sam Rainsy’s pre-commune election comments that a vote for the ruling Cambodian People’s Party would be traitorous to Cambodia.

“It is a very serious [allegation] that CPP voters are traitors,” Hun Sen said, adding that 61 per cent of people had voted for the party.

Tensions over the border demarcation flared on June 17 when the government announced it had no choice but to give two undisclosed villages to Vietnam.

This would mean keeping two other villagers in Kampong Cham province that the former Indochina colonial administration had said belonged to Vietnam, it said.

The “final” Vietnam border post was erected just days later, despite more than 20 remaining to be planted in the ground.

SRP lawmaker Son Chhay wrote a letter to National Assembly President Heng Samrin in June inviting the premier to answer questions related to the border and the plans to cede the two villages.

The letter also called on Hun Sen to explain the positioning of border post 314, between Kampot province and Vietnam, which the SRP claims had cut Cambodians from their land.

SRP lawmaker and spokesman Yim Sovann said yesterday his party would welcome Hun Sen to the National Assembly.

“We will wait and see what he says. We have a lot of questions related to the villages disconnected from Cambodia and Vietnam. We would like the government to answer those questions,” he said.

Sovann said the SRP wanted a frank and open discussion on the topic rather than the prime minister talking for four hours.

“We want the National Assembly to allow questions and debate – in the past, we have not been allowed this.”

Fears that Cambodian land along the border is being swallowed up by Vietnam have played a central role in the SRP’s campaigning in recent years.

Rainsy lives in self-imposed exile in France after being sentenced to more than 10 years in prison for pulling up a border demarcation post and publishing a Google map claiming to show land Vietnam has encroached upon.

Hun Sen said yesterday that the party Rainsy had formed through a merger with the Human Rights Party was much ado about nothing.

“The storm is in a clay pot; be careful or the clay pot will be broken,” he said during his speech to the graduates.

“It has not affected [the CPP] at all. Democratic Movement for National Rescue. Rescue whom now?”

Hun Sen said Cambodia didn’t need to be rescued, adding that the CPP has nothing to fear from the new party.

“A loss plus a loss equals a loss,” he said in a veiled reference to the two parties’ commune election performances.

The prime minister also mocked the DMNR’s plans to lobby abroad for Rainsy’s return.

“They [have sought] international pressure. What pressure? What is the pressure?” Hun Sen asked, maintaining that the opposition leader was fairly tried and sentenced. “What did they create the law for? The guilty individual must be convicted.”

Sovann said he would let the Cambodian people respond to Hun Sen’s remarks at the 2013 election, but said the prime minister’s reaction was a sign the DMNR had rattled the ruling party.

“I want to confirm that His Excellency [Sam Rainsy] is a hero in the Khmer people’s heart,” Sovann said. “Normally, if [DMNR] did not have any political influence, politicians would not react. I believe that this merger has a lot of political influence.”

To contact the reporters on this story: Vong Sokheng at [email protected]

Meas Sokchea at [email protected]

With assistance from Shane Worrell