Police cracked down on a rally Monday aimed at celebrating opposition leader Anwar Ibrahim's formal return to politics, halting him midway through a speech to an estimated 40,000 supporters.

Anwar was making his first public speech since last month's general elections to jubilant opposition members who had gathered for a countdown until midnight, when a legal ban that prevents Anwar from holding political office expires.

The celebration came to an abrupt halt when about a dozen policemen interrupted Anwar after he had addressed the rally for nearly half an hour and forced him to stop.

Supporters, who carried banners that read, "Anwar for prime minister," jeered the police.

"Let me tell you, we will rule the country someday," Anwar said after the incident. "So we will set a good example to obey the law."

Officials did not immediately explain why they blocked his speech, but authorities had earlier warned they might break up the rally because Anwar's opposition People's Justice Party did not apply for a police permit.

The celebration had been expected to further galvanize Malaysia's resurgent opposition, which made spectacular gains in March 8 elections, winning an unprecedented 82 of Parliament's 222 seats. It also won control of legislatures in five of Malaysia's 13 states.

Political pundits say Anwar's ambition is to become prime minister, a post that once seemed within his reach when he was deputy to former Prime Minister Mahathir Mohamad in the 1990s.

However, Mahathir sacked him in 1998 in a power struggle. Anwar was expelled from the ruling party, and convicted of sodomy and corruption, charges that he says were politically motivated.

Anwar was released from prison in 2004 after the sodomy conviction was overturned, but the corruption conviction barred him from holding political office until Tuesday.

He said Monday that he could topple Malaysia's ruling coalition immediately if he wanted to because enough government lawmakers have agreed to defect to his side.

"We have the numbers ... Some (government lawmakers) have had discussions with us, but we are not in a hurry," he said.

Anwar stressed that the opposition's main aim is to carry out reforms in the country, ranging from cleaning up the judiciary to ending corruption and ensuring racial harmony.

He said the opposition needs a "a comfortable majority" to carry out the reforms, and is willing to wait. He gave no indication of how long that might take.

Anwar could not contest the general elections because of the ban. But he is expected to run in a by-election soon to enter Parliament to challenge Prime Minister Abdullah Ahmad Badawi, who is under pressure from his own party to take responsibility for the election losses and quit.

Abdullah said Monday that he will eventually hand over power to his deputy Najib Razak, but not immediately. He said he will contest the post of his party president in December before putting in motion a succession plan to install Najib as prime minister.

"Of course I want the transfer to be smooth. That's very important. I do not want to leave the party in a state of chaos. I would not say "Najib, good luck. That's your problem, not mine.' That's not the way," Abdullah said.

Associated Press writers Julia Zappei and Sean Yoong contributed to this report.

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