Cambodia's UN-backed Khmer Rouge tribunal has run out of money to pay the wages of hundreds of workers as contributions from donor countries have dried up, a court spokesman said Tuesday.

None of the more than 300 Cambodians working at the tribunal, from judges to drivers, will be paid this month and may not receive their salaries in February and March either, said Neth Pheaktra.

"We have no money," he said, adding that some judges and prosecutors had not been paid since October.

The funding shortfall does not affect the more than 130 international employees at the war crimes court, whose wages are paid by the United Nations.

Cambodian salaries are paid through voluntary contributions from donor nations such as Japan, France and Australia.

"It affects morale at the court," said Neth Pheaktra. "The people depend on their salaries to support their families and it's not good to go without pay."

Waiting for wages

The court, set up in 2006 to find justice for the deaths of up to two million people during the Khmer Rouge's 1975-1979 rule, is perpetually cash-strapped but this is thought to be longest period of non-payment to date.

The financial woes come as the UN and Cambodia are locked in a very public standoff over the appointment of a new foreign judge who wants to probe two possible new cases that are strongly opposed by the government.

The tribunal has long been dogged by allegations of political meddling and has also been criticised for proceeding too slowly, adding to donor reluctance to stump up more cash, say observers.

Court officials will travel to New York in February to meet with donor countries to discuss the court's budget for 2012-2013, according to Neth Pheaktra.

"We hope the donor countries can provide urgent funding for our staff," he said, adding that the Cambodian side of the court would likely need around $10 million in foreign contributions in 2012, similar to last year.

The court, which has spent around $150 million since it was set up in 2006, has so far completed just one trial, sentencing a former prison chief to 30 years in jail. An appeal verdict in that case is expected on Friday.

A second trial involving the regime's three most senior surviving leaders is ongoing.