BANGKOK — Cambodian and foreign investigating judges issued conflicting rulings on Wednesday on whether a United Nations-backed tribunal, which this month convicted two senior leaders of genocide, should move forward with prosecution of the next potential defendant.

That defendant is Meas Muth, a former Khmer Rouge naval commander, whose potential prosecution has symbolized the tensions between the two parties to the tribunal, which combines Cambodian and international judges and prosecutors.

Under the legal system in which the tribunal operates, investigating judges carry out pretrial investigations and make determinations as to whether cases should proceed against potential defendants.

The Cambodian side has long insisted that prosecutions should end after the completion of the cases against the last two defendants, Nuon Chea, the chief Khmer Rouge ideologue, and Khieu Samphan, the nominal head of state, who were convicted of genocide on Nov. 16.