A $9 billion oil pipeline that became a symbol of the rising political clout of climate change advocates and a flash point in U.S.-Canada relations was officially canceled on Wednesday.

Keystone XL, which was proposed in 2008 to bring oil from Canada’s Western tar sands to U.S. refiners, was halted by owner TC Energy Corp after U.S. President Joe Biden this year revoked a key permit needed for a U.S. stretch of the 1,200-mile project.

Opponents of the line fought its construction for years, saying it was unnecessary and would hamper the U.S. transition to cleaner fuels. Its demise comes as other North American oil pipelines, including Dakota Access and Enbridge Line 3, face continued opposition from environmental groups.

“This is a landmark moment in the fight against the climate crisis,” said Jared Margolis, a senior attorney at the Center for Biological Diversity. “We’re hopeful that the Biden administration will continue to shift this country in the right direction by opposing fossil fuel projects.”

The Keystone XL pipeline was expected to carry 830,000 barrels per day of Alberta oil sands crude to Nebraska, but the project was delayed for the past 12 years due to opposition from U.S. landowners, Native American tribes and environmentalists.

TC Energy owns the existing Keystone oil pipeline, which runs from Alberta to the U.S. oil storage hub in Cushing, Oklahoma, and to the U.S. Gulf, along with a power and storage business. It pledged to ensure a safe termination of the project.

“We remain disappointed and frustrated with the circumstances surrounding the Keystone XL project, including the cancellation of the presidential permit for the pipeline’s border crossing,” Alberta Premier Jason Kenney said in a statement.

Former U.S. President Donald Trump had approved a permit for the line in 2017, but it continued to face legal challenges that hampered construction. Biden had committed to canceling the project during his campaign and revoked the permit soon after taking office.

TC Energy swung to a loss in the first quarter, hit by C$2.2 billion ($1.81 billion) impairment charge related to the suspension of Keystone XL.

Its shares closed largely flat on the Toronto Stock Exchange.