PUTRAJAYA: Malaysia's highest court on Tuesday upheld a sodomy conviction against Anwar Ibrahim, rejecting his appeal in a case that the opposition leader calls a conspiracy and casting fresh doubt over his turbulent political career.

Chief Justice Arifin Zakaria said the Federal Court had dismissed Anwar's challenge against the conviction handed down last March, which found him guilty of sodomising a young former male aide, Mohamad Saiful Bukhari Azlan.

Last year's conviction brought a five-year jail term, but it was not immediately clear whether Anwar would be imprisoned or how long for.

Read: Malaysia's Anwar convicted of sodomy, political future in doubt

The prosecution is seeking a longer sentence, and the session was to resume in the afternoon after a brief adjournment.

Tuesday's decision exhausts all legal paths in Anwar's bid to overturn the conviction.

Sodomy is punishable by up to 20 years in prison in Muslim-majority Malaysia.

The announcement was read out to a stunned courtroom packed with journalists, opposition figures, and Anwar's family and supporters.

Anwar turned around after the announcement to exchange grim hugs with his family.

“What else is new?” he said to them, sarcastically.

Government critics calls the case part of a long-running campaign to destroy Anwar, a former deputy premier who was ousted from the ruling party in the late 1990s and later helped unite a previously divided and hapless opposition into a formidable force.

The ruling is likely a heavy blow to both Anwar and the opposition.

Now 67, Anwar might not emerge from prison until the age of 72 if he serves the full term.

At any rate, under Malaysian law the decision will strip Anwar of his parliament seat, disqualifying him from taking part in the next elections due by 2018.

“It's a day of infamy. It's a shocking decision,” senior opposition parliamentarian Lim Kit Siang told AFP. Several prominent legal observers had said they felt that, in hearings late last year before the Federal Court, Anwar's defence had successfully raised sufficient reasonable doubt over the charge that he sodomised Saiful in 2008.

Human Rights Watch immediately condemned what it called a 'travesty of justice'.

“Prime Minister Najib Razak's government has persisted in its politically motivated prosecution of opposition leader Anwar Ibrahim,” the group's Asia director Phil Robertson said in a statement.

“Allowing this travesty of justice to stand will further undermine respect for rights and democracy in Malaysia. “Hundreds of Anwar supporters gathered outside the court before the ruling, chanting “Reformasi!”, the longtime clarion call of the movement to unseat the country's 58-year-old government, and “Free Anwar!”.

There were no immediate signs of unrest.