Mahathir - who had retired in 2003 as premier but made a comeback in a bid to oust the coalition he once headed - was sworn in on Thursday, becoming the world's oldest elected leader at 92. "After six decades with the Barisan Nasional [National Front] in power, many people will be unhappy, and we don't know what will happen".
The attorney general, Apandi Ali, declined to comment.
The US State Department alleges in civil lawsuits that $4.5 billion was pillaged from 1MDB in an audacious scheme of fraud and money-laundering, and funnelled to the United States where it was used to buy everything from artwork to high-end real estate.
"I take this opportunity to thank all Umno members who have supported and trusted me since I became president of the party". "But it will take time because it will be done through the legal system".
Late on Saturday, Mahathir met Anwar in his hospital room, where he is recovering from a shoulder operation.
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Former central bank Governor Zeti Akhtar Aziz was named to a "council of elders".
Still, moving against 1MDB and Najib may not be straightforward.
"This shows that the pendulum can swing back from authoritarianism", said Bridget Welsh, a professor of political science and Malaysia specialist at John Cabot University in Italy. "So this would be a threshold that have to be resolved in any review by the new government".
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In their last five matches , they have conceded more than 200 twice and more than 180 on one other occasion. For KKR , West Indies' Javon Searles has come in place of Tom Curran, whereas Rinku Singh has been left out.
It came after what was believed to be a manifest circulated online showing Najib and his wife were due to board a flight from the airport to Jakarta on Saturday morning.
"The leaders of all the parties have been given the mandate and time to do their meetings and which ministries they want to be in and list their candidates".
While Mahathir's victory represents a remarkable shift in a nation long defined by racial politics that hasn't seen a transfer of power since independence in 1957, some analysts warned those divides remain entrenched in Malaysian society.
The Southeast Asian nation's political landscape has been shaped for almost two decades by a bitter feud between Anwar and Mahathir, whose decision to sack Anwar as his deputy sparked an opposition movement, Reformasi, or Reform, in 1998.
He sacked critics in his government, including an attorney general and a deputy prime minister and muzzled the media.
His coalition suffered a shocking electoral defeat this week that ended its 60 year-rule.
He said his deputy, Ahmad Zahid Hamidi, will take over as president of UMNO, a party that dominates the coalition.
"Maybe this will give us a chance to improve on whatever weaknesses and flaws we must tackle", Najib said.