France says it will not agree to a request by the French Polynesian president, Oscar Temaru, to dissolve parliament and hold fresh elections.
The minister in charge of overseas territories, Brigitte Girardin, gave the reply less than a day after Mr Temaru put the request to President Jacques Chirac.
She says the French council of state is yet to decide whether to annul the results of the May elections after the opposition claimed that there had been irregularities.
Mr Temaru sought fresh elections after the opposition submitted two motions of no confidence - backed by a majority of MPs - which have to be voted on within two days.
Mr Temaru has been trying to woo rebel independent Noa Tetuanui back into the coalition fold in a last-ditch bid to defeat the challenge.
But, in an open letter, Mr Tetuanui says Mr Temaru's government is inexperienced and incompetent and Mr Temaru should resign.
Mr Tetuanui, part of the new Te Ara group, also criticises his former colleagues for failing to return land to what he calls its true owners.
Coalition MPs and others close to politics say Mr Tetuanui, who was elected in June under the coalition's Union for Democracy banner, is a traitor for defecting.
But the coalition's spokesperson, Claude Marere, says it still hopes to win him back.
"We are talking, we are still [in] relations, by friends, by parents, by families, with Mr Noa Tetuanui, one of the three independents [who has] come from the majority. We are still in contact with him. And we are not very sure but there is the possibility that the motion will not succeed."
Meanwhile, a peaceful demonstration is planned by women to be held outside the assembly tomorrow morning.
Women, including politicians Nicole Bouteau and Tea Hirshon, are to have a sit-in in protest at the motions being tabled.
Reports say France has decided to deploy mobile riot squads to Tahiti amid security concerns.