Defense lawyers in Cambodia's Khmer Rouge genocide trial filed a complaint Monday accusing Prime Minister Hun Sen of interfering in the proceedings.
Two lawyers for Nuon Chea alleged in a criminal complaint at Phnom Penh Municipal Court that Hun Sen and others in the government had blocked some witnesses from testifying and interfered with the defendants' right to a fair trial.
Previous similar challenges on side issues have failed to affect the proceedings.
Keo Ramy, a spokesman for Cambodia's Cabinet, said the government has not interfered in the tribunal's work and that Nuon Chea's lawyers were just carrying out a delaying tactic.
Nuon Chea, the No. 2 Khmer Rouge leader, is to go on trial with three other defendants late next month. The U.N.-backed tribunal is seeking justice for an estimated 1.7 million people who died of starvation, exhaustion, lack of medical care or torture during the communist Khmer Rouge's 1970s rule.
The four defendants have been indicted on charges of war crimes, crimes against humanity, genocide, religious persecution, homicide and torture.
Hun Sen has publicly chided and threatened the tribunal several times, saying it should not extend its prosecutions beyond the four people to be tried next month and one who has already been convicted. He says more trials could be divisive and even lead to civil war. Many believe, however, that Hun Sen fears his political allies could face indictment.
Some human rights groups accuse the U.N. of bending to Hun Sen's will at the cost of true justice.
Earlier this month, Siegfried Blunk _ the tribunal's German judge responsible for indictments _ resigned, alleging that government interference in the investigation of new cases could give the impression he was bowing to pressure.
Blunk defended his record, blaming government pressure for the lack of new cases. He cited Cambodia's information minister as saying in May that if investigating judges wanted to probe new cases, "they should pack their bags and leave."