Thousands of scientists joined Monday to accuse the Trump administration of trying to erode the Endangered Species Act in favor of commercial interests with a plan to revamp regulations that have formed a bedrock of U.S. wildlife protection for over 40 years.

The extraordinary critique of the administration's proposal, which was unveiled in July, came in an open letter addressed to Interior Secretary Ryan Zinke and Commerce Secretary Wilbur Ross from three associations representing 9,000 professional biologists.

A separate letter similarly condemning revisions proposed to endangered species policies was signed by 273 leading university scientists from around the country.