Transcript
Major cracks in the O'Neill government appeared last month when the prime minister's close ally James Marape resigned as Finance Minister.
This week, Mr Marape announced he was also resigning from the PNC, the biggest party in parliament since 2012.
"I stepped down so that future cabinet... the manner in which cabinet is run, I felt, is not consultative, is not... in many key critical issues. And most of you will know I stepped out on the back of Papua LNG discussions."
The government's move last month to sign the Papua LNG Gas project agreement with French company Total has been a clear factor in resignation by several MPs.
Meanwhile, some MPs appear to be wavering over their political allegiances.
The governor of West Sepik province, Tony Wouwou, was earlier this week photographed with opposition MPs ahead of their announcement of plans to table a motion of no-confidence agasint Mr O'Neill.
Media reports that Mr Wouwou had defected to the opposition were followed by reports later in the day that he'd re-joined the government.
The governor maintains he never intended to resign from the PNC or the government.
"I was not going to the opposition. I was visiting my colleagues, my open MPs. I have three MPs (from his province) in the opposition. So I went down to sit with them and talk with them. But I was not jumping over the fence, trying to cross over the floor to the opposition. I'm still with the current government."
This week the PNC held a caucus meeting in which they claimed to still have 38 MPs in the 111-seat parliament.
Mr O'Neill says he's confident he will have the numbers to defeat a motion.
While at the start of the week the opposition said it had 26 MPs, it was confident that more would join it in the days ahead.
South Fly MP and opposition member Sekie Agisa says the government is going to change because a lot of MPs share the same frustrations.
"Since the prime minister took office, we have not seen under his government any development in the province. So I'm taking a stand that if this government is not doing anything for the province, then why would I support the government."
Meanwhile, the country's oldest party, the Pangu Pati, is reported to have split.
For months, the party's MPs have been at loggerheads with its executive, which has expelled Finance Minister Sam Basil as its leader after his move in 2017 to bring the party into government.
Earlier this week, Mr Basil indicated that all 15 Pangu MPs would resign from the party and establish themselves under a new party name.
However the MPs are split over what direction to take, with around half poised to return to the opposition, and the rest staying with Mr Basil in government.
While the make-up of parliament remains fluid, more resignations are expected in the coming days ahead of a planned motion next week.