Malaysian opposition leader Anwar Ibrahim said he would call Prime Minister Najib Razak and his wife as witnesses in his sodomy trial due to begin on Tuesday, accusing them of conspiring against him.
Anwar, who was sacked as deputy premier and jailed on similar charges a decade ago, criticised the case as "the machinations of the dirty, corrupt few" as he arrived at court accompanied by his wife and daughters.
Anwar said he had evidence that his accuser, 24-year-old former aide Mohamad Saiful Bukhari Azlan, had met with Najib and his wife Rosmah Mansor at their home shortly before he lodged a police report.
"We want to subpoena Najib and Rosmah as witnesses because they were personally involved in the conspiracy and frame-up," he told reporters.
"It is politically motivated," he said of the trial which he maintains is a plot to end his political career and neutralise the threat he poses to the Barisan Nasional coalition government.
The court adjourned until 0630 GMT to allow defence lawyers to attempt to delay the trial while they pursue manoeuvres including a bid to obtain prosecution evidence such as medical reports and CCTV footage.
"They should not proceed with the matter. Anwar should be allowed to exhaust all appeals," defence lawyer Sankara Nair told reporters. "Everything should be disposed of, to ensure a fair trial."
Anwar's lawyers will now meet with Malaysia's chief justice to seek his support for another postponement in the trial, which was originally due to begin last July.
As the hearing got underway, up to 300 opposition supporters marched into the High Court building and stood on the staircase in the main lobby, yelling their battlecry of "Reformasi" or "Reform."
"We are here to demonstrate against the injustice that Anwar is facing, we will be here every day until this matter is resolved," said parliamentarian Tian Chua.
The courtroom was packed to capacity, with reporters, legal observers, and diplomats from the US, Japan and European nations who are keeping a close watch on the proceedings.
Human rights group Amnesty International has criticised as "dirty tricks" the charges against Anwar, who in his first trial was brought to court with a black eye after a vicious beating from the police chief.
Saiful's father, Azlan Mohamad Lazim, said at the court that his son was present on Tuesday and "ready and prepared to testify in the case."
He declined to comment on Anwar's allegations over the meeting with Najib, but the prime minister last year told a press conference that Saiful did call on him to allege he had been sodomised by Anwar.
Anwar rallied the opposition to unprecedented gains in 2008 elections, seizing a third of parliamentary seats in the most potent challenge yet to the Barisan Nasional which has ruled for half a century.
The charismatic 62-year-old, a married father of six, was a celebrated finance minister before being sacked in 1998 amid a policy row with then-premier Mahathir Mohamad during the Asian economic crisis.
He was convicted of sodomy and corruption but after spending six years behind bars, the sexual misconduct charge was overturned and he was freed in 2004.
The trial looms after a tumultuous few months in Malaysian politics, with the opposition beset by infighting and the government struggling to handle a religious row that has seen places of worship firebombed and vandalised.
Najib has battled to defend Malaysia's image as a moderate Muslim-majority nation after a caning sentence against a young woman caught drinking beer and other cases that have raised fears the country is being "Islamised."
The Anwar trial, which defence lawyers say could drag on for eight months, poses a major challenge for both sides on the political divide, and will be a high-profile test of Malaysia's much-criticised justice system.