The 27-page document released by the tribunal shows Duch expressing remorse.
Rare photos taken by American journalist Elizabeth Becker are now on display in Phnom Penh.
A meeting on funding is scheduled at the UN for Feb. 24, according to a donor country diplomat who spoke on condition of anonymity.
Nuon Chea has so far been the only one of three leaders on trial for atrocity crimes to repeatedly address the court in his defense.
Through an attorney, victims of the regime told the UN-backed court of crimes of torture and execution.
The three leaders—Noun Chea, Khieu Samphan and Ieng Sary—are charged with atrocity crimes that include genocide.
Cambodian deputy prosecutor Veng Huot said Khieu Samphan had attained the movement’s highest rank through two decades of resistance.
In an e-mail interview, Royce said he has sent a letter to Secretary of State noting his concern for an ongoing culture of impunity.
The life sentence for Khmer Rouge torture chief Duch is a “good example” to society, a researcher said this week.
The two statements are an escalation of a series of public splits
between Cambodian and international judges at the UN-backed court...
Nuon Chea said he wanted to see original documentation and hear recordings of his own voice before giving the accusations credence.
In it are dozens of photographs from a 1978 trip Becker took with other journalists at the invitation of Khmer Rouge leaders.