The approval was expected. Conservative Prime Minister Stephen Harper has been a staunch supporter of Enbridge's proposed Northern Gateway pipeline after the U.S. delayed a decision on TransCanada's Keystone XL pipeline that would take oil from Alberta to the U.S. Gulf Coast.
Enbridge's pipeline would transport 525,000 barrels of oil a day from Alberta's oil sands to the Pacific to deliver oil to Asia, mainly energy-hungry China.
There is fierce environmental and aboriginal opposition to the project and legal challenges are expected. Opponents fear pipeline leaks and a potential disaster on the pristine Pacific coast.