Six small French Polynesian parties have joined forces to rally support for the ousted President, Gaston Tong Sang.
The grouping is pushing for fresh general elections this year amid the deepening rift among the politicians who've been advocating close links with France.
The Tahoeraa Huiraatira Party is reportedly ready to expel Mr Tong Sang after several of its members voted with the opposition Union For Democracy last month.
The parties backing Mr Tong Sang claim to have about 13 members in the assembly and describe themselves as the third force and the only opposition left.
Meanwhile, the newly elected President, Oscar Temaru, is to present his new government within the next hour.
The French government is expected to outline its plans this week aimed at shortening the term of the current assembly in Tahiti for fresh elections to be held.