US Deputy Secretary of State John Negroponte, above, could announce funding for the Khmer Rouge tribunal Tuesday, Prime Minister Hun Sen said.

The US could declare additional funding for the cash-strapped Khmer Rouge tribunal as early as Tuesday, Prime Minister Hun Sen said Monday, following talks with US State Department Deputy Secretary of State John Negroponte.

"Tomorrow, you will know," Hun Sen told reporters Monday night. "Maybe [Negoroponte] will declare the amount of the donation to the Khmer Rouge tribunal."

Hun Sen declined to say what amount the US would pledge, and a US Embassy spokesman would not confirm an aid pledge.

A potential announcement of US funding comes amid mounting financial pressure on the hybrid Cambodian-UN tribunal, where the Cambodian side has had much of its funding frozen by donors in the wake of corruption allegations.

US officials have said they will not fund a tribunal that does not meet international standards, and the tribunal has taken some measures to investigate allegations of corruption.

No allegations have been proven, but a 2007 UNDP audit found mismanagement and questionable hiring practices on the Cambodian side.

Tribunal officials say they will need around $50 million, with $40 million coming from donors and $10 million from Cambodia, before the end of 2009.

Negroponte, who is one of the highest-ranking State Department to visit post-war Cambodia, signed a $24 million agricultural deal with Hun Sen Monday night, following a brief trip to the temples of Angkor Wat Sunday and talks with opposition leaders Sam Rainsy and Kem Sokha Monday.

His visit was the mark of a strengthening relationship between the two countries that has meant the resumption of direct US aid.

The talks were "a positive process from the US government," Hun Sen said. "Now we can say it is time for the pregnant elephant to give birth."

Negroponte is expected to address the media before he leaves Tuesday morning.