Nathalie Normandeau, Quebec's deputy premier and natural resources minister, is leaving politics for what she calls a more stable life.

"Political life is very demanding," she said. "I leave without any bitterness."

Normandeau made the announcement Tuesday afternoon at a press conference in Quebec City.

She cited personal reasons for her departure, a decision the 43-year-old said she came to after much reflection.

As deputy premier, Normandeau was seen by many as a possible successor to the provincial Liberal party leadership. Standing beside Premier Jean Charest, she acknowledged there's never a good time to make such an announcement.

"Mr. Charest always tells us, before politics there is life," she said. "Today, I choose to realize this great principle . . . to do other things, but also to have a private life as well."

Normandeau, 43, was first elected to the provincial legislature in 1998. She served as municipal affairs minister before taking over the natural resource portfolio in June 2009.

She was most recently responsible for Plan Nord, an ambitious multi-billion dollar plan to develop the province's northern region.

Normandeau faced heavy criticism from environmentalists and landowners over the past year for her defence of Quebec's fledgling -- yet highly contentious -- shale-gas industry.

She was also attacked by the opposition Parti Quebecois for maintaining a relationship with former Montreal police chief Yvan Delorme, who himself has come under fire amid corruption allegations.

Charest has not announced who will replace Normandeau as deputy premier.

with files from Canadian Press