Prime Minister Hun Sen likened opposition leaders to a gang of thieves confessing to their crimes after opposition head Sam Rainsy said his party would tame its attacks on the ruling Cambodian People’s Party regarding the Vietnam border issue.

“A gang of thieves destroying the stability of this country who have come to confess: that is Mr Sam Rainsy and his party,” the premier said during a radio interview on Monday.

“While they shake our hands, they step on our toes and use the culture of dialogue to destroy the royal government.”

The comments came only hours after Rainsy had visited jailed opposition lawmakers at Prey Sar prison outside Phnom Penh, telling reporters that the Cambodia National Rescue Party would tone down its public criticism of the CPP over alleged Vietnamese encroachment on the border.

“If we speak out publicly, it does not result in a gain,” Rainsy said at the time.

But Prime Minister Hun Sen said staying quiet would not be enough.

“To settle the doubts of the royal government and the CPP, Sam Rainsy’s party and Mr Sam Rainsy himself must correct all the dishonest points about the royal government and [the CPP], so the culture of dialogue can go ahead,” Hun Sen said.

During the months that the CNRP has politicked about the border, a number of opposition leaders and activists have been imprisoned.

Earlier this month, three CNRP activists were jailed on accusations that they participated in a violent protest at Freedom Park more than a year ago.

They joined 11 other party members who were recently handed lengthy prison sentences on “insurrection” charges stemming from the same protest.

On Saturday, Sam Rainsy Party Senator Hong Sok Hour was arrested for posting an allegedly fake section of a border treaty between Cambodia and Vietnam and an accompanying video on Facebook. He faces a potential sentence of 17 years.

CNRP spokesman Yim Sovann did not respond to Hun Sen’s comments directly yesterday, saying CNRP leaders had done everything to resolve the border issue honestly.

“I do not want to respond. I only want to think of how we can find a way to preserve national unity and solidarity and not let foreign countries look down on us,” he said.

One of the strongest blows against the CNRP came when Hun Sen personally called for Sok Hour’s arrest last Friday.

Three days later, military police stormed his house and escorted him to jail on charges of forgery and incitement.

Yesterday, a coalition of 13 NGOs called Sok Hour’s arrest – undertaken despite his parliamentary immunity – part of a “far-reaching and systematic attack on dissent and democracy in Cambodia”.

The statement said Hong Sok Hour’s arrest needed to be seen in the context of other political developments, such as the recent passing of the law on non-governmental organisations and yesterday’s arrest of three environmental activists from conservation group Mother Nature.

“The Royal Government of Cambodia is undertaking a campaign to shut down the dissenting voices that provide the strongest opposition – political opponents, civil society organizations, trade unions, and ordinary people using social media – by exercising complete control over the judiciary and by introducing oppressive laws that violate international human rights standards,” the statement says.

While the opposition has absorbed multiple blows in recent weeks, one political analyst said the CPP’s campaign could be seen as a sign of its weakness.

Future Forum founder Ou Virak said Hun Sen was trying to intimidate the opposition into submission, although Sam Rainsy’s agreement to back off the border dispute for now could give the CNRP respite until the national elections in 2018.

“Hun Sen seems to have lost much popularity and is moving towards losing power [in the elections], and it’s probably like this that he is trying to cause fear during the final round.”