Independent Vanuatu MP Ralph Regenvanu says he and three other MPs who have signed a solidarity pact will support Maxime Carlot Korman's bid to be Prime Minister.
Following the release of official results from last week's general election, Mr Korman's Vanuatu Republican Party says it has the support of enough MPs to form the next government.
But a rival bloc based around the two parties with the most MPs - the Vanua'aku Party, which won 11 seats, and the National United Party with 8 - also claims it has the support to command a majority in the 52-seat parliament
They are in talks with several smaller groupings over possibly joining the VP/NUP coalition.
However Ralph Regenvanu's group has ruled out working with them.
"We've signed a solidarity agreement and we're a bloc of four. Part of our solidarity agreement is sixteen policies that we want implemented and we'll go with whoever can implement them and Korman has agreed to implement them and to give us two ministries (Finance and Internal Affairs). So we're with Korman. And of course while there's a history of corruption with Korman, VP and NUP are the same or worse."