By Colin Packham
SYDNEY (Reuters) - The parliament of Papua New Guinea (PNG) will elect a prime minister at the end of the week, lawmakers said on Monday, in an election marred by poor organization and opposition accusations of electoral roll irregularities.
With no political party able to clinch enough seats to form a government, analysts said the outcome remained too close to call, stirring voter frustration that could trigger more unrest in the resource-rich South Pacific nation.
On Saturday, incumbent Prime Minister Peter O'Neill was invited to try to form a coalition government, with his party on track to win the largest number of seats, although fewer than half the 56 needed, forcing him to woo coalition partners.
"The ruling People's National Congress and the main opposition, the National Alliance party, each believe they have the numbers, it is very close," said Jonathan Pryke, a research fellow at Australian think-tank the Lowy Institute.
Wednesday's vote to determine PNG's next parliamentary speaker will offer a clue to which party has the necessary support to win the prime ministerial vote, analysts say.
However, both decisions are unlikely to be made by a full complement of lawmakers, as vote counting continues after polls had to be extended when a large number of voters were unable to cast ballots.
PNG voters went to the polls to elect a new 111-member parliament in late June, but use of an electoral roll dating from 2012 meant many voters could not vote, forcing an extension of a two-week window.
Most of PNG's nearly 8 million people live at subsistence level on islands, atolls and in remote mountain villages, despite the country's mineral wealth, evidenced by energy giant Exxon Mobil's $20-billion LNG plant.
"It is most unlikely that all seats will have been declared by Friday," said a source close to the main opposition National Alliance Party, who declined to be named as he was not authorized to talk to the media.
"The numbers won't matter, the prime minister will be determined by the majority present on the day."
Voter dissatisfaction with the election triggered sporadic violence nationwide, but O'Neill's re-election could stoke more tension, as many are disenchanted by corruption allegations against him that he denies.
The winner faces a tough economic task, with the 2016 budget deficit of 34 percent of GDP having doubled from 2012, worsened by a slump in energy prices.
A 2016 drought crippled farming and halted production at the largest copper mine, by cutting off river transport and so fuel supply.
PNG must also grapple with fallout from plans to close an Australian-run detention center home to just over 800 refugees, mainly from South Asia and the Middle East.
(Reporting by Colin Packham; Editing by Clarence Fernandez)