In the last words the Khmer Rouge tribunal will hear before a verdict is issued in Case 002/02, former Khmer Rouge head of state Khieu Samphan said he was not a murderer on Friday and denied knowledge of grave crimes against humanity that occurred under the regime, in which an estimated 1.7 million Cambodians lost their lives.

His rare comments bring the court proceedings to a close in the second trial of Samphan and former Brother Number Two, Nuon Chea, for crimes including murder, extermination, and genocide.

“I know that they really suffered,” Samphan said, referring to the Civil Parties, who are victims of the regime represented in the courtroom.

“I also heard when they spoke to me, sometimes referring to me as a ‘murderer’. How could it be otherwise? Since this court’s inception, it has done everything in order to let you, the Civil Parties, to refer to me as someone who has the responsibility for all the sufferings … inflicted upon the victims by the Khmer Rouge.”

“But the term ‘murderer’; I categorically reject it.”

Samphan, 85, fumbled a pen into his shirt pocket before taking the stand to read his statement. He became animated at times, thrusting his finger to drive home certain points.

“The Communist Party of Kampuchea leaders did not exterminate our people,” he said. He described the “self-genocide” accusations as Vietnamese propaganda.

“It has invented the unacceptable idea of the Cambodian genocide. And if this happens, we will all observe the shameful and tragic irony, in which Vietnam will ask those – that is, those leaders who allowed it to take the reins of our country, namely, the Big Brother and the only “gang of the three” of the [Cambodian People’s Party] – to present an official apology on behalf of Cambodia for the genocide of the Vietnamese.”

Khieu Samphan types on a laptop at the Khmer Rouge tribunal earlier this month. ECCC

His comments appear to refer to current Prime Minister Hun Sen, who defected from the Khmer Rouge 40 years ago and returned, backed by the Vietnamese military, to oust the regime. That event was taken to mythological heights earlier this week when the premier re-enacted the crossing into Vietnam.

Samphan denied any knowledge of forced marriages, discrimination between “base” and “new” people, or the slaughter of minority groups under the regime.

“I will not say more about things that I did not know, because so far everything I have said in my attempt to understand the tragic events of my country is held against me in order to conclude my responsibility,” Samphan said, licking a finger to turn the page.

“I heard during the hearings that life was hard in co-operatives. I do not doubt it. However those who consider themselves in senior positions believed that they had the right to accuse and had the right to punish other people.”

In the first phase of their trial, the pair was declared guilty of crimes against humanity, including murder, in an appeal judgment handed down last year.

Samphan stressed yesterday that the country was ravaged by war when the Khmer Rouge took power in 1975, and that famine, drought and intensified conflict against the Vietnamese created a perfect storm in Democratic Kampuchea.

“Our country was emerging from an unprecedented crisis. All areas in our countryside had been pounded by American bombs,” he said, adding there was an “urgency” to rebuild the economy.

“In order to rebuild and defend our country the only force we had was the strength of people,” he said.

“The wish of the Communist Party of Kampuchea, at the time was not to subject the population to slavery, for the sole benefit of Mr Pol Pot. However, that is exactly the fable told by the Co-Prosecutors. That is wrong.”

The truth, he said, was that the communist regime hoped to gradually improve the livelihoods of the people, where they would have an abundance of food to eat and develop industries beyond agriculture.

Samphan, who offered a sampeah to the Buddhist monks at the court – a group that was forced to disrobe under his rule – said he wanted to “bow to the memory of all the innocent victims”.

“But also to all those who perished by believing in a better ideal of the bright future, and who died during the five-year-war under the American bombardments and the conflict with the Vietnamese invaders,” he said.

“Their memory will never be honoured by any international tribunal.”

His co-accused, Nuon Chea, declined to make any final comments today before the court, with his lawyer Victor Koppe saying Chea decried the tribunal as a “deeply flawed and broken institution” and a product of “victor’s justice”.