Phnom Penh, Jan 8 (IANS): The UN war crime tribunal Thursday resumed its hearing against two top leaders of Cambodia's erstwhile Khmer Rouge regime who have already been convicted in another case.

"All parties are present," the tribunal's president Nil Nonn said.

Khieu Samphan, 84, the regime's former head of state, appeared in the courtroom, as Nuon Chea, 89, the chief ideologue of the Communist Party of Kampuchea, followed the proceedings on a video link from a holding cell due to his poor health, Xinhua reported.

The tribunal began the second and final trial for Khieu Samphan and Nuon Chea for genocide charges in October, but had been subsequently adjourned due to the boycott of defence teams.

The two former Khmer Rouge leaders were among the few surviving leaders of the regime that was responsible for the deaths of an estimated 1.7 million people from starvation, torture, execution, and massacre from 1975 to 1979.

In August 2014, the two ex-leaders were given life sentences for crimes against humanity after their first trial at the tribunal.

They have appealed against the verdicts.