Ten years after being forced from power by charges of sexual misconduct, Anwar Ibrahim was sworn in as the leader of the Malaysian opposition today and repeated his promise to drive out the government of the prime minister, Abdullah Badawi.

“I am glad to be back after a decade. I really feel vindicated. I feel great,” Mr Anwar said after being sworn in as a member of parliament and immediately elected as leader by the three party opposition coalition. “Clearly the prime minister has lost the mandate of the country and the nation.”

Mr Anwar won a convincing victory in a by-election on Tuesday in the state of Penang, just four months after the expiry of a ban on standing for public office. It was in 1998 that he was precipitated from the job of deputy prime minister after being accused of corruption and sodomy with his male driver, a grave crime in Malaysia.

He always insisted that the charge had been trumped up by the ruling United Malay National Organisation (Umno), because of the challenge which Mr Anwar, the deputy prime minister, was planning against his boss, the then prime minister, Mahathir Mohamad.

In 2004, the sodomy conviction was overturned by Malaysia’s top court and Mr Anwar was released. But the corruption charge stuck with the result that Mr Anwar was barred from standing for parliament until April this year. In March, however, the opposition coalition, of which he was de facto leader, achieved its greatest ever electoral success, coming close to toppling Umno and undermining the leadership of Mr Abdullah.

Then in June he was accused once again of the same crime of sodomy of which he had been acquitted – this time with a 23-year-old male aid. Mr Anwar has vehemently denied the accusation, with which he has been formally charged, and insisted that it is another attempt by the government to cripple him politically.

Having returned to active politics, he has set himself the task bringing a vote of no confidence against the government by 16 September, the 45th anniversary of the formation of the modern Malaysian state. To do this he must turn the opposition 82 seats into a majority of the 222 seat parliament, by persuading over 30 members of Umno’s National Front coalition to switch sides.

“There is no threat from Anwar, he has won in a by-election and he becomes just another MP,” Mr Abdullah’s home minister, Syed Hamid Albar, said today. “Since the March 8 elections till now we have [seen] nothing but politicking... but [the defections] haven't happened. They are waiting for it to happen but it hasn't happened - good luck to them.”

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