As the Khmer Rouge tribunal moves toward trials of five jailed leaders, the special courts will face problems in donor funding and credibility, a leading monitor said this week.

The tribunal will need to convince donors to make a "significant" investment, said Robert Varenik, acting director of the Open Society Justice Initiative.

To do so, the courts will need to show "the greatest possible transparency," he said.

Tribunal officials say they need about $114 million more to fund the tribunal, to supplement what began as a $56 million effort.

Donors are considering further funding, following some progress, such as the arrest of five leaders, public hearings of two, and the march to trial for all. But donors are also wary of allegations of corruption and mismanagement within the special courts.