Cambodia's acting opposition leader has left the party headquarters where he has taken refuge for more than four months to avoid arrest, choosing to register to vote in next year's local elections.

Kem Sokha was recently sentenced to six months in prison for refusing to honor a court summons to testify in connection with a sex scandal in which he is involved. He contends the legal actions are part of a government plot to cripple his Cambodia National Rescue Party.

Party president Sam Rainsy is in self-imposed exile to avoid serving a prison term on a defamation charge he contests. Critics say Prime Minister Hun Sen is manipulating the courts to weaken the opposition's challenge to his ruling Cambodia People's Party in next year's polls.