Khmer Rouge leader Pol Pot's deputy, Nuon Chea, has claimed that Cambodia's most hated regime of the 1970s, was not for the people of his country, and that those facing trial in court were being misjudged by history.

Chea told a court that Vietnamese troops were responsible for the deaths of up to 1.7 million Cambodians, and not his Maoist-inspired regime.

Frail but defiant, the 85-year-old who once served as the regime's main ideologist took to the stand at the UN-backed tribunal in Phnom Penh for the first time to declare he had devoted his life to serving his country. Hundreds had packed the court to hear him speak.

"I don't want the next generation to misunderstand history. I don't want them to believe the Khmer Rouge are bad people, are criminals," The Independent quoted Chea, as saying.

He added: "These war crimes and crimes against humanity were not committed by the Cambodian people. It was the Vietnamese who killed Cambodians."

Chea is one of three elderly men on trial for their roles in the 1975-79 reign of the Khmer Rouge.

Estimates have suggested that up to 1.7 million people were either executed or died of starvation or disease as the regime forced people to live in agricultural labour camps.

Nuon Chea, along with Khieu Samphan, 80, the former head of state, and 86-year-old Ieng Sary, the one-time Foreign Minister, are all charged with crimes against humanity, genocide, religious persecution, homicide and torture.

They deny the charges and Ieng Sary has indicated he will not co-operate with the tribunal.

A fourth senior figure, the Social Affairs Minister Ieng Thirith, was recently declared unfit for trial because she has dementia. (ANI)