The mayor of the French Polynesian capital, Michel Buillard, has resigned from the Tahoeraa Huiraatira party after nearly a quarter of a century of membership.
Mr Buillard's move comes just days before the second round of the early general election to choose a new assembly for five years.
In his resignation letter, he gave no reason for the move.
Mr Buillard had served as a minister in various territorial governments led by the party leader, Gaston Flosse, and last year he was elected for a third term as one of the territory's two members of the French assembly.
In the first round of voting nearly two weeks ago, the Tahoeraa only won half the number of votes secured by the To Tatou Aia led by Gaston Tong Sang.