Papua New Guinea's opposition has formally given notice that it will move a motion of no confidence in the government.
A parliamentary committee will now decide if and when the motion will be debated in parliament, which the Post Courier says is likely to take a week.
The opposition leader, Don Polye, says he has met all the requirements to submit a motion, and insists he has the numbers for it to work.
The prime minister, Peter O'Neill, has called the motion desperate, ambitious and not in the best interests of the nation, but for the personal interest of Mr Polye.
He says the country faces huge challenges with El Nino and bleak economic conditions, which the parliament should instead be focussing on.
Papua New Guinea is the third Melanesian country to pursue a motion this week, with one due to be debated in Solomon Islands tomorrow, and Vanuatu's opposition seeking to gather the numbers for one there.