A federal judge in Montana halted the progress of the controversial Keystone XL pipeline Thursday over concerns the Trump administration did not properly consider its impact on climate change and on vulnerable animal species on the brink of extinction.

President Donald Trump called the action a “disgrace” and a “political decision” in comments to reporters before departing for his trip to Europe.

The action marks a setback for what had become a signature energy achievement for Trump, who has touted his speedy approval of the pipeline almost immediately upon taking office in January 2017.

That speedy approval of a cross-border permit by the State Department, however, did not meet the standards of the National Environmental Policy Act and the Endangered Species Act, according to U.S. District Court Judge Brian Morris. The judge found the environmental reviews were deficient in their analysis of the project’s effect on greenhouse gas emissions and endangered species, among other areas.

“The Department’s 2017 conclusory analysis that climate-related impacts from Keystone subsequently would prove inconsequential and its corresponding reliance on this conclusion as a centerpiece of its policy change required the Department to provide a reasoned explanation,” Morris wrote in his decision. “The Department instead simply discarded prior factual findings related to climate change to support its course reversal.”

The action also marks the latest court intervention blocking the construction of pipeline infrastructure after environmental groups filed lawsuits alleging the federal agencies approving permits failed to properly analyze their effect on climate change and the surrounding environment.

“The Trump administration tried to force this dirty pipeline project on the American people, but they can’t ignore the threats it would pose to our clean water, our climate, and our communities,” said Sierra Club Senior Attorney Doug Hayes in a statement.

It remains unclear whether the administration will appeal the decision, but it is expected to do so. A comment was not immediately available from the State Department, through which the final approval was granted.

The Keystone pipeline, proposed by Calgary-based TransCanada, has become an environmental flashpoint dating back to the Obama administration. President Barack Obama ultimately rejected the cross-border permit needed for the project to advance, citing climate change concerns. Trump has used his quick approval of the project as evidence of his dedication to helping cut red tape for domestic fossil fuel projects.

TransCanada has not made a final decision about whether it will go forward with construction of the pipeline. The economics of the oil market and the costly production needed to pull the oil out of the Canadian tar sand fields led the company to delay its decision.

Regardless, the State Department awarded a cross-border permit for the project on March 24, 2017. A coalition of environmental groups, including the Sierra Club, Center for Biological Diversity, Friends of the Earth, the Natural Resources Defense Council, Bold Alliance and the Northern Plains Resource Council, filed a lawsuit within days.