Prime Minister Hun Sen yesterday launched a searing personal attack on Cambodia National Rescue Party president Sam Rainsy, saying he was the “son of a traitor” and nothing like Aung San Suu Kyi, whose party this week trounced Myanmar’s military junta in historic elections.

Responding to recent comments by Rainsy suggesting the success of Suu Kyi’s National League for Democracy (NLD) foreshadowed the premier’s own downfall in the 2018 national election, Hun Sen blasted the CNRP leader in videos and text posted on his Facebook page, and warned of possible legal action against the opposition’s leadership.

“I cannot keep calm because of this insult by the son of a traitor,” Hun Sen wrote, noting the differences in Myanmar and Cambodia’s political landscapes.

“[I] appreciate the success of the opposition in Myanmar . . . but the opposition leader in Cambodia . . . again took this opportunity to attack me and again destroyed the culture of dialogue that, recently, was being fixed [thanks] to the meeting set up between Deputy Prime Minister Sar Kheng and Sam Rainsy,” a reference to recent high-level talks to defuse political tensions following an attack on two CNRP lawmakers last month.

Hun Sen then turned his attention to Rainsy’s father, Sam Sary, a former top government official and ambassador to England in the 1950s who fell out of favour with then-head of state Prince Norodom Sihanouk and fled Cambodia when his name was attached to an alleged coup plot.

He said the opposition leader could not compare himself to Suu Kyi because her father, Aung San, considered the father of Myanmar’s independence from colonialism, was a “patriot”, whereas his was a “traitor”.

“Your Excellency called me a dictator, and today I called you son of a traitor, but it is not me who insulted your family . . . I am following the word used by the former regime,” he said.

“I know in our modern society it is difficult to be accepted [as a traitor], but I cannot change the historic traitor to [a nationalist],” he wrote, later adding: “The leaves do not fall far from the base of the tree.”

In a video posted later in the day, Hun Sen then warned Rainsy and his deputy Kem Sokha that they faced legal action for “defamation” over recent comments by Rainsy in Japan calling for international help to ensure free elections because the CPP wanted to avoid the “democratic process”.

“This time, don’t expect to run out of the country if you [Rainsy] still continue to abuse [the law],” he said, after also raising the spectre of legal action over anti-government rallies following the disputed 2013 election.

Further, in a bid to seemingly embarrass the CNRP leader, Hun Sen released the alleged text of a personal apology Rainsy sent him on October 29, three days after CNRP lawmakers Nhay Chamroeun and Kong Sakphea were brutally beaten outside parliament during the tail end of a pro-Cambodian People’s Party rally against Kem Sokha.

The message, which sits awkwardly next to Rainsy’s initial accusation that Hun Sen had orchestrated the attack using “fascist methods”, reminds the premier of the family dinner the political rivals enjoyed in July, when relations between the parties were at a high point under the so-called “culture of dialogue”.

“I strongly regret [my commentary] whether or not it was caused by misinterpretation . . . I would like to apologise to Samdech, if I made you disappointed [even] unintentionally,” he wrote.

Rainsy, who is in Japan, did not respond to requests for comment yesterday, but re-issued a statement standing by the apology as “good manners”.

Political tensions remain high after the lawmakers’ bashing and subsequent ousting of Kem Sokha as the parliament’s first vice president.

The prime minister has denied the CPP organised the attacks, for which three soldiers have been charged.

He has, however, acknowledged the initial 2,000-strong protest that preceded the violence was organised in response to opposition protests that met him on recent state visits to New York and France.

Only last week, both Hun Sen and Rainsy pledged to continue the so-called culture of dialogue, an agreement – stemming from last year’s deal to end the CNRP’s boycott of parliament – to end the charged and combative rhetoric that has for so long characterised Cambodian politics.