President Donald Trump is ratcheting up the pressure on major drugmakers to bring their US prices in line with the far lower ones available to patients in other countries — though industry experts don’t expect the pharmaceutical companies to acquiesce.

European pharmaceutical stocks slumped, continuing a selloff that started with US-listed peers after President Donald Trump escalated his campaign to pressure drugmakers to lower prices in the country.

President Donald Trump sent letters to the leaders of 17 major pharmaceutical companies outlining how they should slash U.S. prescription drug prices to match those paid overseas, the White House said on Thursday.