French Polynesia's opposition grouping has lost a member, with Clarenntz Vernaudon breaking away from the Oscar Temaru-led camp.
Mr Vernaudon gave no reason for his decision but says he will not join the ruling coalition and stay with the other independent assembly member.
The latest move has left Mr Temaru two members short of a majority as he has vowed he will lodge a no confidence motion in the government of Gaston Tong Sang before the end of the month.
There are opposition claims that Mr Vernaudon acted under pressure from the ruling Tahoeraa Huiraatira Party but it has denied any involvement.
The ruling coalition is itself still one vote short of a majority but managed to pass the 2010 budget last month.