Prime Minister Hun Sen today threatened to boycott next month’s Asean-Australia Special Summit in Sydney – and to “beat” demonstrators outside who burn his image – after apparently being supplied leaked telephone calls between opposition members predicting forthcoming international “pressure”.

“To the extremist group, please be careful. Seiha listens every day,” he said in a speech to garment workers, apparently in reference to a pro-government social media personality who frequently leaks secretly recorded conversations damaging to opposition figures.

The premier appeared to be warning the Cambodia National Rescue Movement, a group founded by ex-opposition leader Sam Rainsy that the government has branded a “terrorist” network.

According to Hun Sen, CNRM members said on Tuesday in a private phone call shared with him that the United Nations would put pressure on the Cambodian government, as would a collection of Asean countries and Australia at the upcoming Asean summit in Sydney in March.

He then appeared to threaten to not attend the proceedings or to veto any joint statements, saying that “if there is no Hun Sen, there will be no Asean”.

“I’ll just give the reason that in 2018 I cannot go abroad because I am busy with the election,” he said, referring to this year’s scheduled ballot. “This means Australia won’t be able to hold the meeting. If there is no consensus it is impossible.”

The premier said he still planned to be there, but reserved the right to veto any joint statement if met with pressure or resistance.

Miguel Chanco, lead Asean analyst for the Economist Intelligence Unit, said the summit would likely go on without Hun Sen in the event of a boycott.

“Certainly, China – Cambodia’s main ally – would not want to see a complete boycott as Hun Sen’s government has traditionally defended Beijing’s interests in such meetings,” he said in an email.

However, Chanco noted that even if Hun Sen does himself boycott, a delegation could veto any measures in his place.

Charles Santiago, head of the Asean Parliamentarians for Human Rights, said the premier was likely “bluffing”.

“If Hun Sen chooses to boycott the Australia-ASEAN summit, it will be his loss more than anyone else’s and will only serve to further isolate his regime internationally,” Santiago said in an email, accusing the premier of “throwing a tantrum . . . to avoid scrutiny”.

In his speech, the premier then went on to threaten any potential protesters in Sydney who might demonstrate against him.

“I would like to send a message, do not burn my photo. If you burn my photo, I will follow you home . . . I will follow you and beat you at home,” he said.

Political analyst Lao Mong Hay said that Hun Sen had been “very angry” when previously met with protesters abroad – for example in 2016 at the US-Asean Summit – and was likely using threats to preempt demonstrations in order to avoid losing “a lot of face”.

Hun Sen stayed on the topic of wiretapping in his speech, saying that a phone conversation involving doctors at Kantha Bopha Children’s Hospitals had also been handed over to him by Seiha. In it, the premier claimed, the doctor discusses the possibility that Hun Sen’s daughter Hun Mana might take over the donor-funded hospitals, despite lacking in expertise.

“I know your face, name, residence and that you are a brain surgeon; you should not be a fool like this,” Hun Sen said.

“Seiha heard that and shared to me . . . The Hun family is not the family for you to look down on . . . Somebody who uses the title of the Hun family must face the law as well.”

Wiretapping is illegal under Cambodia’s Criminal Code, carrying a sentence of one month to one year in prison, though the government is allowed to record conversations as part of an investigation. Seiha typically posts leaked material on social media but does not appear to have posted the conversations mentioned by the premier.

Updated: 7:57am, Thursday 22 February 2018