The proposed 1,200-kilometere Mackenzie Valley natural gas pipeline would move about 1.2 billion cubic feet of natural gas a day from gas fields in the Mackenzie Delta on the Beaufort Sea coast to Alberta to power oilsands production.

Canada and Northwest Territories governments issued a formal reply to the 176 recommendations of a panel that studied the proposed C$16.2 billion pipeline to take gas from Canada's Arctic to southern markets November 15, 2010.

"The governments have rejected key recommendations from the joint review panel that were carefully designed to control cumulative impacts from induced development, ensure wise end-use of the delivered gas, and would have required independent reporting on government implementation," said Keith Ferguson, Ecojustice staff lawyer.

"The Mackenzie Gas Project is economically, socially and environmentally unsustainable," said Sheila Muxlow, director of Sierra Club Prairie.