Papua New Guinea's veteran Prime Minister Michael Somare has stepped down so he can face a tribunal over allegations of official misconduct against him, his office told AFP on Tuesday.
Somare, who has led the impoverished island nation for 16 of its 35 years of independence, will step aside until a leadership tribunal can hear allegations that he failed to lodge several annual financial statements in the 1990s.
Somare "said he will now voluntarily step aside and allow the deputy prime minister, Sam Abal, to assume (the) full function and responsibility of the office of prime minister while he attends to clearing his name," a statement signed by Somare said.
"Sir Michael's voluntary action will ensure that the proceedings take place unhindered," the statement issued late Monday said.
Former foreign minister Abal, who was appointed last week, will act as prime minister for the duration of the tribunal, established despite a bid by Somare to block the public prosecutor from advising PNG's chief justice to do so.
"While the supreme court has yet to give the prime minister an opportunity to be heard on his reference, the public prosecutor has proceeded to make a referral," the statement said.
"However, the prime minister respects the due processes and will continue to avail himself to hearings."
If found guilty by the tribunal, potential punishments range from fines to removal from office, Australian public broadcaster ABC reported.
But Somare's aides have dismissed the investigation as politically motivated, while the leader said he had not been given opportunity to defend himself against the allegations since they were first filed in 2008.
The wily 74-year-old political survivor said he was the victim of a "gross injustice" because he had been unable to find a judge available to hear his application for an injunction against the formation of the tribunal.
"This is gross injustice to any citizen who is deprived of their basic right to be heard in a competent forum," he said in the statement.
Somare, one of the Asia-Pacific region's longest-ruling leaders, is currently serving his fourth term as prime minister after becoming PNG's first leader after independence in 1975 and being re-elected in 1982, 2002 and 2007.
His stepping aside marks the climax of two weeks of high political drama in PNG.
Somare last week suddenly reshuffled his cabinet, installing Abal as his deputy, while the supreme court ruled Friday that the re-election of the country's governor-general was invalid, sparking a fresh crisis.
Somare has been under pressure to resign all year, with the veteran leader thwarting a parliamentary no-confidence vote in July triggered by the defection of some MPs only by abruptly adjourning proceedings until November.
At the time, parliament was outraged at the adjournment, and in wild scenes Somare reportedly crossed the floor to tell an opposition lawmaker "you're dead meat".
His spokeswoman and daughter, Betha Somare, said last week her father was confident he would not lose his position as leader of Papua New Guinea, which is on the cusp of a resources boom thanks to the development of gas deposits.
Somare has courted controversy, earning neighbouring Australia's wrath in 2006 when he ignored an extradition request for then-Solomon Islands attorney general Julian Moti to face child sex charges.
In May 2010, Somare apologised after branding anti-corruption activists "mentally retarded", and in June, PNG banned reporting and discussion of environment law changes that could allow a Chinese miner to pump waste out to sea.