(Bloomberg) -- U.S. President Donald Trump says environmentalists and Indian tribes are understating his authority in trying to block the permit he issued to revive the stalled Keystone XL oil pipeline project.

Lawyers for the Trump administration says foes of the project have put forward a “blatant mischaracterization” of what the permit does, along with “a grossly lopsided view of the Constitution’s allocation of authority between the President and Congress,” according to a filing Thursday in federal court in Montana.

In an earlier challenge to the $8 billion project, a federal judge in November faulted the State Department’s environmental analysis. In March, Trump issued a new permit for the pipeline to cross the U.S.-Canada border, and administration officials sought to reassure critics that they will conduct environmental reviews and assess impacts on endangered species as required by law.

The lawsuit targeting the March permit was brought by a nonprofit representing indigenous people and a conservation advocacy group that contend the pipeline poses a grave threat to the environment and human health.

To contact the reporters on this story: Peter Blumberg in San Francisco at pblumberg1@bloomberg.net;Tom Korosec in Dallas at tkorosec@bloomberg.net

To contact the editors responsible for this story: David Glovin at dglovin@bloomberg.net, Peter Blumberg

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