President Donald Trump on Monday revived a controversial policy that aims to slash drug costs by tying the prices of some medicine in the U.S. to the significantly lower ones abroad.Trump signed an executive order including several different actions to renew that effort, known as the “most favored nation” policy. He did not refer to specific nations, but signaled that he would target other developed countries because “there are some countries that need some additional help, and that’s fine.””Basically, what we’re doing is equalizing,” Trump said during a press event on Monday. “We are going to pay the lowest price there is in the world. We will get whoever is paying the lowest price, that’s the price that we’re going to get.”White House officials did not disclose which medications the order will apply to, but said it will impact the commercial market as well as Medicare and Medicaid. They said Monday’s announcement will be broader than a similar policy that Trump tried to push during his first term, which only applied to Medicare Part B drugs.Officials added that the administration will have a particular focus on drugs that have the “largest disparities and largest expenditures,” which could include popular weight loss and diabetes treatments called GLP-1 drugs.It’s unclear how effective the policy will be at lowering costs for patients. In a social media post on Monday, Trump claimed drug prices will be cut by “59%, PLUS!”But Trump during the press event claimed drug prices may fall even more, between 59% and 80%, or “I guess even 90%.”Shares of U.S. drugmakers rose Monday. Merck’s stock added more than 4%, while Pfizer and Amgen climbed more than 2%How Trump’s drug pricing order will wo …