Louise Poirier, a veteran Gatineau councillor and chair of the STO, is resigning from her municipal post.

Poirier, who represents Or´┐Że-du-Parc, served her notice during a private meeting with Gatineau Mayor Marc Bureau on Monday. She will officially leave office August 10.

Bureau issued a news release about Poirier's sudden departure on Monday, thanking the councillor for her service.

A spokesperson for Poirier told CTV Ottawa she will not publicly announce the reason for her resignation until Wednesday.

Poirier was elected to council in 1999.

A byelection to replace the councillor will be held next fall.