KUALA LUMPUR - Malaysian opposition leader Anwar Ibrahim suffered another setback in his sodomy trial Wednesday as he was denied access to statements by his accuser which he hoped would force the case to
collapse.

Anwar, a former deputy premier who was sacked and jailed on separate sex and corruption counts a decade ago, is accused of illicit sex with 25-year-old Mohamad Saiful Bukhari Azlan, who was an aide in his office.

On Tuesday his lawyers, who have lost a series of legal manoeuvres to derail the trial, tried to undermine the basis of the case by pointing out he was charged with a consensual act while Saiful claimed he was assaulted.

They applied for all statements that Saiful has made about the alleged incident, but were knocked back by Judge Mohamad Zabidin Mohamad Diah who said the attorney-general was entitled to press a lesser charge.

Defence counsel Karpal Singh, who is seeking a stay of the trial while he appeals the decision, said the issue was critical because it could see Saiful impeached and his testimony discredited.

"If the application is successful, (Saiful's) testimony becomes worthless and the prosecution cannot proceed," he said. "The testimony of their star witness turns to stardust, nothing remains."

Anwar, a 62-year-old father of six, says the charges have been trumped-up in a political conspiracy aimed at ending his career after his opposition alliance made major strides in 2008 elections.

Saiful has confirmed he met with Prime Minister Najib Razak four days before lodging a police report over the alleged sexual encounter which he said took place at a Kuala Lumpur apartment on June 26, 2008.

"At first, he was shocked. He (Najib) was very sceptical when I told him that Anwar sodomised me," Saiful said Wednesday, adding that the premier had not advised him to lodge a police report.

The prime minister, however, has repeatedly denied any involvement in the case.

Sodomy, even among consenting adults, is illegal in Malaysia - a conservative Muslim-majority country. If convicted, Anwar could face up to 20 years imprisonment.

Human Rights Watch has urged Malaysia to drop the charges against Anwar, condemning the case as a "charade of justice" and saying his lawyers have also been blocked from preparing a thorough defence.

Anwar spent six years in jail on the original sodomy and corruption allegations until the sex conviction was quashed in 2004.