The head of Cambodia’s Human Rights Party has blasted a Cambodia National Rescue Party lawmaker for daring to compare Sam Rainsy to a martyr for the cause of southern Kampuchea Krom, a section of southern Vietnam which Cambodian nationalists have long claimed to be part of the Kingdom.

Son Soubert, the president of the Human Rights Party – which merged with the Sam Rainsy Party to form the Cambodia National Rescue Party in 2012 but still holds positions at the local level – issued a strongly worded statement on December 30 condemning CNRP lawmaker Eng Chhay Eang.

Chhay Eang’s offence was comparing Sam Rainsy to Oknha Son Kuy – a provincial governor purportedly decapitated by the Vietnamese in 1841 for resisting an invasion.

During a Radio Free Asia interview on December 19, Chhay Eang noted that Son Kuy’s death did nothing to stop Vietnamese mistreatment of Cambodians, as he referenced Rainsy’s decision to remain in self-imposed exile following an arrest warrant.

Soubert’s letter urged Chhay Eang to apologise to the “millions of Khmer Krom”, the ethnically Khmer inhabitants of southern Vietnam, “for looking down on their hero”.

“His Excellency Sam Rainsy is the leader of one single party and takes responsibility for that one party only; he is not an army chief or governor taking responsibility for his citizens against an invasive enemy of tens of thousands,” the letter wrote.

Son Soubert’s late father, the prominent Cambodian statesman Son Sann, claimed to be a grandson of Okhna Son Kuy.

Eng Chhay Eang, who is currently in Canada, could not be reached for comment.