The Biden campaign on Monday affirmed that if he’s elected president, Joe Biden would rescind President Trump’s permit to allow the Keystone XL oil pipeline to cross the U.S. border.

The Obama administration had rejected the pipeline twice. But, two months into his presidency, Trump reversed the decision and directed the State Department to approve Keystone XL.

In 2017, after reviewing its impact on the environment and climate, the State Department approved the permit to build the $8 billion transnational pipeline that would carry up to 830,000 barrels of crude oil daily from Canada to Nebraska.

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“That denial of science ends on day one of a Biden presidency. When Biden takes office, we will have nine years left to stop the worst consequences of climate change, and Biden won’t waste a single day,” the former vice president’s campaign policy director, Stef Feldman, said in a statement Monday.

“Biden strongly opposed the Keystone pipeline in the last administration, stood alongside President Obama and [then-Secretary of State John] Kerry to reject it in 2015, and will proudly stand in the Roosevelt Room again as president and stop it for good by rescinding the Keystone XL pipeline permit,” Feldman continued.

Less than two weeks after the pipeline project got underway in April, a judge canceled a key permit, saying the U.S. Army Corps of Engineers failed to adequately consider effects on endangered species such as pallid sturgeon, a massive, dinosaur-like fish living in rivers the pipeline would cross.

The Keystone pipeline, part of a system set to include the Keystone XL pipeline, leaked 380,000 gallons of oil in North Dakota last October.

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The Trump administration has been appealing the ruling from a federal judge in Montana.

Fox News' Allie Raffa contributed to this report.