The B.C. government is set to announce a ban on coal-bed methane gas drilling in the Sacred Headwaters area. (David Zalubowski/Associated Press)

The B.C. government has confirmed a ban on oil and gas development in the Sacred Headwaters region of northwestern B.C. 

"As part of a tripartite agreement, Shell Canada is immediately  withdrawing plans to explore for natural gas in the Klappan by relinquishing its tenures," the province said in a release.

"In addition, the Province of British Columbia will not issue future petroleum and natural-gas tenure in the area."

A four-year ban on oil and gas exploration in the area was set to expire Tuesday.

Shannon McPhail, the executive director of the Skeena Watershed Conservation Coalition, says announcement is a welcome relief.

"There are no words to even describe how we're feeling about this right now," she told CBC News. "This has been a long road of 10 years of working on this and I think it has been a huge victory."

The moratorium has prevented Shell Canada from doing exploratory drilling in the area, which is home to the headwaters of three salmon-bearing rivers: the Skeena, Nass and Stikine.