Locked out of the hall he was supposed to be using, Mr Anwar spoke from the top of a van in a darkened parking lot.

"The government is trying to keep the people away from me," he said.

"I am not afraid. No matter what happens, whether in prison ... I will still strive, I will still fight, I will not step down."

Supporters rally around Anwar Ibrahim

He again denied the charges of sexual misbehaviour and endangering state security that were levelled against him at the time of his dismissal by the Prime Minister, Mahathir Mohamed.

He repeated that he was the victim of a high-level political conspiracy.

On Saturday, Mr Anwar was given a warm welcome even in Jitra, the birth place of Dr Mahathir, where tens of thousands of people wanted to hear his speech.

Mr Anwar also spoke to thousands of supporters in his hometown of Cherok Tok Kun in the nearby state of Penang, asking them to dismiss the allegations and stand by him.

First rallies outside Kuala Lumpur

This weekend's rallies are the first time Mr Anwar has made public speeches away from his residence on the outskirts of Kuala Lumpur.

After his sacking, Mr Anwar remained in his house, addressing crowds of up to 6,000 from there, but then took to the road at the weekend to publicise his claims of innocence against the accusations to a wider audience.

Prime minister Mahathir Mohamad : Wait and see attitude

The government appears to be adopting a wait and see attitude over the meetings.

Quoted in a local newspaper, Dr Mahathir said no action will be taken against the meetings if they are peaceful. But he said he was ready to take action if the rallies disrupt public order.

Dr Mahathir also gave veiled warnings to Mr Anwar's supporters who remain members of the United Malays National Organisation (UMNO) - the key party of the ruling National Front coalition led by Dr Mahathir.

He is reported to have said that their support for Mr Anwar will surely affect them when it re-evaluated their loyalty to the party.

Mr Anwar, who was expelled from UMNO after being sacked, has said he does not intend to join the opposition.