The French Polynesian government has ordered the demolition of the headquarters of the traditionally dominant Tahoeraa Huiraatira Party of Gaston Flosse.
The party's building in central Papeete has been found to be in an alarmingly dangerous state, containing toxic materials that are difficult to remove.
The premises accommodate some businesses which will also have to move.
The Tahoeraa reportedly bought the building eight years ago.
The party, which was founded by Gaston Flosse, won most seats in the last election, but expulsions, resignations and rifts within its ranks have left it as a de-facto opposition group.