Several thousand rallied outside a court in Kuala Lumpur to show support for Anwar Ibrahim, opposition leader and Malaysia's former deputy prime minister, who is due to hear the verdict on his sodomy trial on Monday.

The session was due to begin at 9:00 am, but some supporters arrived at the Kuala Lumpur High Court before 6.

They chanted slogans and held pro-Anwar placards as the opposition leader arrived at the court, accompanied by his family, including his wife and all six children.

Despite several hundred reports against the rally were lodged across the country, Malaysian police gave green light by allowing opposition and Anwar's supporter to assemble at a parking lot in front of the court complex, where heavy police force and barriers were deployed on Monday.

The Opposition had said earlier it would draw 100,000 supporters to rally for Anwar. Azmin Ali, deputy president of Anwar's People's Justice Party, promised that the gathering would be peaceful.

Anwar is tried for allegedly sodomising his 27-year-old former assistant at a condominium unit in Kuala Lumpur in 2008.

If convicted, he will be jailed for up to 20 years.

This was the second time Anwar is charged with sodomy, a crime in the Muslim-majority country.

In 1998, Anwar was dismissed as deputy prime minister and later convicted for sodomy and corruption.

He was released in September 2004 and resumed his political career as an opposition leader, leading the opposition parties to hold five states in Malaysia's 2008 general election.