Japan on Monday injected nearly $1.4 million in additional fund assistance to support the Khmer Rouge tribunal in Cambodia, according to the Japanese Embassy in Phnom Penh.

The disbursement was made to the U.N. side of the court, and brings to $82.73 million Japan's total contributions, about 36 percent of the total international contributions since the inception of the Extraordinary Chambers in the Courts of Cambodia in 1997.

"Japan considers that it is important for the ECCC to proceed with the trial in a fair, efficient, and (expeditious) manner, given the advanced age and frail health of the persons charged and in order to achieve the long overdue justice for the people in Cambodia," the statement said.

Two former Khmer Rouge leaders — Nuon Chea, known as Brother No. 2, and Khieu Samphan, former head of state of the regime — were sentenced and convicted on Aug. 7 to life in prison by the trial chamber of the U.N.-supported tribunal. Both of them have appealed the verdict.

They are the first members of the regime leadership to face justice. Pol Pot died in 1998, long before the ECCC was established. In 2010, the trial chamber sentenced Khmer Rouge prison chief Duch to life in prison.

The Khmer Rouge is blamed for the deaths of at least 1.7 million Cambodians from 1975 to 1979.