Outgoing Prime Minister Abdullah Ahmad Badawi prepared to meet Malaysia's king on Thursday to hand in his resignation in a planned transition of power to his deputy Najib Razak.
A senior government official familiar with the plan told AFP Abdullah would have an audience with King Tuanku Mizan Zainal Abidin at about 0200 GMT.
The official, speaking on condition of anonymity, said that Abdullah "will inform the king of his intention to resign and tell him that Najib is ready to assume the country's top post."
Najib has told reporters he will be sworn into office at a ceremony Friday, completing a transfer of power triggered by the ruling coalition's disastrous showing in elections a year ago.
Analysts say he faces an enormous challenge to rejuvenate his United Malays National Organisation (UMNO), which has floundered since those elections, and cushion the country from the worst effects of the global meltdown.
He faces his first big test next Tuesday with three by-elections that will be seen as a referendum on support for his fledgling leadership.
"He will inherit a divided party with trust in the government at its lowest ebb and a strong opposition," political analyst Shahruddin Badaruddin told AFP earlier.
He said Najib's challenge would be "to unite the fractured elements of the party."
Najib has an impeccable pedigree as the son and nephew of two former prime ministers, but he has been dogged by controversy and Shahruddin said he had to stem the allegations against him.
He has repeatedly denied opposition allegations connecting him to the 2006 slaying of the mistress of his close aide -- a Mongolian woman whose body was blown up with military-grade explosives.
"He must end all the rumours and allegations about the Mongolian case once and for all," Shahruddin said.
"It has affected his image locally and internationally," he added. "As long as these rumours persist, it will make it hard for him to do what needs to be done."
The 55-year-old is the longest serving cabinet minister, entering politics at 23 after the 1976 death in office of his father Abdul Razak, the country's second prime minister.
Mild-mannered and always impeccably dressed, he took a degree in economics at the University of Nottingham in England before returning to Malaysia in the mid-1970s to take on key posts at the central bank and the national oil firm.
A nephew of the nation's third premier Hussein Onn, Najib held a number of cabinet posts in the 1980s and 1990s, during which he modernised the military as defence minister before becoming deputy premier in January 2004.
His path to the premiership was all but cleared last week when Abdullah -- who had been criticised as weak and ineffective during his six years in office -- handed him the UMNO leadership.
UMNO leads the National Front coalition which has ruled Malaysia since its independence from Britain in 1957.
Abdullah, 66, announced his retirement plan last October after coming under heavy fire for the election debacle, when the opposition won an unprecedented one third of seats in parliament.
The opposition also took control of five states, but the coalition wrested back one state, Perak, in February after defections upset the delicate balance of power.