President Donald Trump signed a sweeping executive order Monday morning that promises to crack down on “unreasonable or discriminatory” practices by foreign countries that result in Americans paying far higher costs for prescription drugs.

"I will be instituting a MOST FAVORED NATION'S POLICY whereby the United States will pay the same price as the Nation that pays the lowest price anywhere in the World," the president posted Sunday on his social media site, pledging to sign the order on Monday morning at the White House.