US officials will deliberate on funding for the Khmer Rouge tribunal in January, a government envoy said Friday, following a three-day visit.

The US ambassador at large for war crimes, Clint Williamson, said he was impressed by the progress of the tribunal, especially with the arrests of five former leaders of the regime, but that no decision had been made in the US on funding.

"The arrest of the five suspects, I think, was a very, very positive move," he said. "The adoption of the rules of the court, all these things are good indicators that [the tribunal] is headed in the right direction."

US officials have said in the past they were looking at allegations of mismanagement and corruption and their impact on the international credibility of a tribunal.

"There is a budget proposal that is going forward. This will probably be assessed in New York in January," Williamson said.

Tribunal spokesman Reach Sambath said he hoped Williamson would take with him the positive developments of the tribunal as US officials make their decision.