Vanuatu's Foreign minister, Moana Carcasses, says they are negotiating with the prime minister's office to offer his junior coalition group another cabinet seat.
The president of the Alliance for the Development of Vanuatu, Maxime Carlot Korman, has said he would pull out of the coalition government this week if he wasn't offered a ministerial portfolio.
Mr Carcasses, who is also leader of the Greens which is part of the ADV, says two cabinet seats are preferred to the one they currently have.
He says a committee has been set up to determine how they can fit Mr Korman into cabinet which is restricted to 12 MPs.
"We would like to propose to a leader like honourable Donald Kalpokas, who is today the current minister of education, to become maybe the next president of the republic. So, that's one idea we are negotiating at the moment - if he becomes the next president of the republic, then there is a vacant ministry then and maybe Mr Korman will take the position or another ministry, we don't know."
Mr Carcasses says the prime minister is likely to agree to the ADV having two cabinet seats because he wants to change the constitution.
He says in order to do that, the prime minister needs the support of two thirds of the 50 MPs in parliament.
Mr Carcasses says the coalition currently has 31 MPs.