A lawsuit filed in Canadian courts says the government isn't honoring an endangered species act in its review of the Northern Gateway oil pipeline.

Environmental advocacy group Ecojustice filed a lawsuit against the Canadian government on behalf of the Sierra Club and four others. The lawsuit charges the government hasn't implemented the Species at Risk Act in order to protect threatened species that may live along the proposed route for the Northern Gateway oil pipeline.

Pipeline company Enbridge aims to build the $6 billion pipeline to carry as much as 585,000 barrels of so-called tar sands oil per day from Alberta to British Columbia for export to Asian markets.

"While failing to meet its legal responsibility under the Species at Risk Act, our government has nevertheless found plenty of time and resources to vigorously promote the Enbridge pipeline proposal," said George Heyman, executive director of the British Columbia chapter of the Sierra Club.

Ecojustice said the Species at Risk Act is good policy "on paper" but hasn't been implemented properly. The lawsuit seeks a court order to force Harper's administration to outline recovery strategies for species potentially threatened by Northern Gateway.