Three parties in the Somare-led government could hold the balance of power if a no-confidence motion is moved against the Prime Minister in the November sitting of Parliament.
In another development, it has been hinted Opposition Leader Peter O'Neill may stand aside as the alternate prime minister in favour of former prime minister Sir Mekere Morauta.
The Post Courier newspaper reports this would give the Opposition a better chance of wresting power from the government.
It says highly-placed sources at the centre of the political manoeuvres named the three parties as the Melanesian Alliance, PNG Party and the Pangu Pati.
Sir Mekere leads the PNG Party.
The Petroleum Minister Sir Moi Avei is leader of the Melanesian Alliance while the leadership of Pangu Pati is now being battled out in court between another former prime minister and Foreign Affairs Minister Sir Rabbie Namaliu and Gulf Governor Chris Haiveta.