With Mr Anwar's trial on charges of corruption and sexual misconduct on hold for a regional summit in the capital, Kuala Lumpur, his lawyers have argued that his dismissal was an abuse of power by the prime minister.

They have said it is "illegal and violates the constitution" because only Malaysia's king, Yang di-Pertuan, has the power to formally fire ministers.

"I have decided to dispute the decision to sack me as deputy prime minister and finance minister by Prime Minister Mahathir Mohamad," Mr Anwar said in a statement read out by his wife Wan Azizah.

When Mr Anwar was dismissed on 2 September, Dr Mahathir said he was morally unfit to perform his duties. Mr Anwar was subsequently arrested on 20 September. His trial began on 2 November. So far only seven of the 52 prosecution witnesses have taken the stand.

Apec summit

Meanwhile, United States officials have said that the American Secretary of State, Madeleine Albright, hopes to meet Mr Anwar's wife, in what will be seen as a highly significant gesture.

Mrs Albright is visiting Malaysia for the Asia Pacific Economic Co-operation (Apec) summit which begins next week.

Security is tight for the Apec summit in Kuala Lumpur

At least three leaders due to attend the Apec meeting, including US President Bill Clinton, have said they will not meet Dr Mahathir for bilateral talks in protest at the treatment of Mr Anwar, who appeared in court with a black eye after his arrest.

Mr Anwar's trial is scheduled to resume on 23 November, five days after the summit ends. His close associates are expected to be working to cause maximum embarrassment for the Malaysian Government during the meeting.

Protesters focused the world's attention on popular discontent in Malaysia during the Commonwealth games in Kuala Lumpur in September.