Around 270 Cambodian staff at the Khmer Rouge war crimes tribunal have gone two months without pay and are threatening a walkout.
The workers at the UN-backed courts have not been paid since November and have no contracts.
"They gave us some information about our salaries but it didn't really explain anything," said one staff member, declining to be identified as he is not authorised to speak to the media.
"We are angry and discouraged," he said, adding that he and many of his colleagues planned to walk out if they were not paid within the next two weeks.
Under an agreement with the United Nations establishing the special UN-Cambodian tribunal, the Government has an obligation to fund the Cambodian side.
It has paid $USD 1.8 million a year in general costs for utilities, security, healthcare and transport, as well as the courthouse, which it owns.
The government has used outside contributions to pay the estimated $USD 9.3 million a year wage bill but sources close to the issue say big foreign donors like Japan are overstretched and want Cambodia to come up with more cash.
Staff, however, do not see that happening.
"The Government won't pay these salaries. They just want this court to shut down," a staff member said. "By creating this situation, they just want to embarrass the UN."
Government spokesman Ek Tha said Cambodia was appealing to outside donors for help.
"Its all about interpretation," Ek Tha said. "The UN receives money from donors to pay their staff, Cambodia is the same."
The funding dispute puts the spotlight on the commitment of the government, which has been accused of interfering behind the scenes to put the brakes on the court and limit the scope of investigations that could implicate powerful political figures.
Prime Minister Hun Sen, himself a former Khmer Rouge guerrilla who defected to the regime's eventual conquerors, Vietnam, has said he would "not allow" any new indictments and would be happy if the United Nations packed up and left.
Between 1.7 and 2.2 million people, almost a quarter of Cambodia's population, died between 1975 and 1979 under the ultra-Maoist Khmer Rouge regime.
The leader Pol Pot died in 1998, but his sidekicks are now on trial for murder and crimes against humanity, among other charges.
The court is not just facing financial troubles.
Two international investigating judges quit in the space of six months in 2011 and 2012, over what they said was political interference.
Many Cambodians now fear the three remaining defendants in the court's second case - Nuon Chea, Ieng Sary and Khieu Samphan - may not live to hear a verdict.
The three former Khmer Rouge leaders, who all deny responsibility for the mass deaths during their rule, are in their 80s, and all have been in hospital suffering from fatigue and dizziness in the past month.
A fourth defendant, Ieng Thirith, Pol Pot's sister-in-law, was declared unfit for trial last year because she was suffering from Alzheimer's disease.
Only one verdict has been delivered since the court was set up in 2005 - life imprisonment for Kaing Guek Eav, better known as 'Duch', the chief of the notorious Tuol Sleng prison, where as many as 14,000 people may have been executed.