A senior member of Papua New Guinea's National Alliance Party, says it would be disastrous for the party if it teams up with the Opposition Leader, Peter O'Neill.
The National newspaper reports that Dickson Tasi is urging the Prime Minister and party chief, Sir Michael Somare, to exercise caution in light of the fact that Mr O'Neill only recently tried to oust the government.
Mr Tasi says the Opposition is only trying to work its way in to make another attempt.
He says Sir Michael doesn't need Mr O'Neill to take him through to the elections in 2007 and he should look instead to those who had stuck by him in trying times.
Mr Tasi included the PNG Party led by Sir Mekere Morauta, the People's Progress Party, the People's Action Party and the National Party.
He says the deputy prime minister's post should go to one of these people.
Suggestions of a grand coalition in PNG have been circulating over the last few weeks.