The move is being challenged in court by the opposition which gained a majority last week following a mass defection of government MPs.

Opposition leader Belden Namah, with a majority of MPs behind him, moved a motion to adjourn parliament to early next month when a grace period on motions of no-confidence lapses.

But Speaker Job Pomat subsequently ruled that the motion had been wrongly entertained by his deputy and recalled parliament.

Former prime minister Peter O'Neill, one of the opposition MPs leading the charge to remove Marape, said the speaker's ruling was flawed.

"Flawed in the sense that in every occasion over the past forty-five years only the members of parliament can adjourn parliament by a resolution and a motion on the floor, when in fact Belden Namah on Friday moved the motion to suspend standing orders,” O’Neill said.

"When you suspend standing orders that means the standing orders do not apply. Fifty-seven members gave him the authority. That is why he moved the motion."

At Tuesday's sitting, parliament achieved a quorum with less than half of all MPs present, when the government passed its budget, without the usual required debate.

O'Neill's legal team has now filed a court application challenging the legality of the sitting, which the opposition was largely unable to attend.

"So Marape and the Speaker are making a mockery of the parliamentary system, the mandate of our people, the democracy that we have enjoyed for the last 45 years," O’Neill said.

While this was happening, the embattled prime minister summoned public service departmental heads, including the police commissioner and defence commander, for a special briefing.

The message he gave was reiterated to the public at large, blaming the current crisis on MPs who he said were prepared to indulge in cut-throat politics at a time when PNG is faced by steep challenges caused by Covid-19.

"So let me at this time encourage our citizens, don't you worry about politics that is taking place,” Marape said.

“Remain focused at your job, leave politics to politicians, get on your life. Public servants and members of our disciplinary services are asked to remain above politics, focus on your job."

Marape dismissed O'Neill's claim that Tuesday's adjournment was illegal. He said just because the opposition decided to leave the capital and form a camp in remote Vanimo doesn't mean government services must come to a standstill.

"Mr O'Neill and his friends in the opposite side of the house are reminded that we will play by the rule, play fair and square.

“And if they're not satisfied, well the court is the place where we can meet. In the meantime, government business runs, we run a government," Marape said.

Marape had the option of adjourning parliament to June, within the last 12 months of parliament's five-year term, when it's not possible to lodge a no-confidence motion. But by instead opting for April, the prime minister has given the opposition a late chance at tabling such a motion.

"I would have played nasty and asked the leader of government business to push parliament into a safer time when there was no vote-of-no-confidence opportunity, for instance after 30 July 2021," Marape explained.

"But we are not stupid running government. We are mindful that parliament is a place of forum. The reason why we pushed parliament to April was to ensure the programs of early 2021 take place - 2021 is an important preparation year for the 2022 national elections."

With last week's political gambit frustrated, O'Neill has kept up the attack on his former close ally's government.

"We are hearing today that they are printing cheques in the Treasury, printing cheques in the Finance Department to use to politically bribe members of parliament,” he said.

“This have never happened before in the history of our country."

Similar accusations are flying in the other direction. Finance Minister Rainbo Paita revealed that, on the eve of his exit from government, Bulolo MP Sam Basil, who was deputy prime minister and national planning minister until he led the defection last week, oversaw a large payout from the supplementary budget prepared to meet the towering challenges of an economy rocked by the pandemic.

According to Paita, the funds allegedly went to MPs in Basil's United Labour Party.

Meanwhile, one of the defectors, William Duma, the incumbent minister of commerce and industry, is now back showing support for Marape again.

Last Friday, after leaving government, Duma cited concerns about government handling of the economy, yet the bulk of his United Resources Party remained with the government.

Now he is back claiming last week was a mistake made while in confusion at the opposition's move.

Duma has form, having switched sides more than once during the lobbying that preceded the ousting of O'Neill as prime minister last year.

The Mt Hagen MP's inveterate flip-flopping means there's no guarantee he won't change sides again, another sign that the political situation in Port Moresby remains fluid.