(The Hill) — President Donald Trump said Sunday he will sign an executive order Monday to cap prescription drug and pharmaceutical prices at the lowest cost offered to any other country.

America has notoriously paid more than other developed nations for the same prescription drugs. But under Trump’s “most favored nation” policy, the president hopes to ensure “the United States will pay the same price as the Nation that pays the lowest price anywhere in the World.”

“Our Country will finally be treated fairly, and our citizens Healthcare Costs will be reduced by numbers never even thought of before. Additionally, on top of everything else, the United States will save TRILLIONS OF DOLLARS,” Trump continued, in a Sunday post on Truth Social.

Trump said he will sign the executive order at the White House at 9 a.m. EDT on Monday. He called the executive order “one of the most consequential Executive Orders in our Country’s history.”

“Prescription Drug and Pharmaceutical prices will be REDUCED, almost immediately, by 30% to 80%. They will rise throughout the World in order to equalize and, for the first time in many years, bring FAIRNESS TO AMERICA!” Trump added in the social media post.

The pharmaceutical industry ripped Trump’s announcement, pointing the finger for high drug prices at pharmacy benefit managers and health insurance companies.

“This Foreign First Pricing scheme is a bad deal for American patients. Importing foreign prices will cut billions of dollars from Medicare with no guarantee that it helps patients or improves their access to medicines. It jeopardizes the hundreds of billions our member companies are planning to invest in America, making us more reliant on China for innovative medicines,” said PhRMA president and CEO Stephen J Ubl.

Politico reported last week that the president planned to sign an executive order directing aides to pursue the “most favored nation” initiative for a “selection of drugs within the Medicare program.”

At the time, Politico reported that details were subject to change and that the president had not yet personally approved the plan.