President Donald Trump speaks to the media prior to departing on Marine One from the South Lawn of the White House in Washington, DC.

President Donald Trump on Monday issued an executive order designed to pressure insurers, doctors and other health-care providers to disclose more information about their prices.

The executive order will direct the Department of Health and Human Services to require hospitals and insurers to disclose negotiated rates for services, as well as provide patients with out-of-pocket costs before their procedures.

"We are fundamentally changing the nature of the health care marketplace," Trump said before signing the order.

Trump said the lack of price transparency has benefited industry giants "greatly" and has cost Americans millions of dollars in health care costs.

Price transparency can "empower" patient choice, Health and Human Services Secretary Alex Azar said in a call Monday with reporters.

"The president has a clear vision for American health care," Azar said. "That's the promise he's made to American patients, and today represents a historic step for delivering on that promise."