The price index idea, which the pharmaceutical industry and many medical providers have vigorously opposed, is still under review from the Office of Management and Budget and may begin as a five-year pilot program next year. But it would apply to only a small subset of the drug market, and would not affect the prices paid for more typical prescription drugs that are sold at retail pharmacies. An executive order on drug prices would most likely have no force of law on its own, but could direct the Department of Health and Human Services to pursue or expand this approach.

Outside of the doctor’s office or hospital, the federal government does not buy many medications itself. Under current law, Medicare’s main prescription drug program farms out its drug purchasing to private insurance companies, and is barred from negotiating with drugmakers directly. The federal government does buy drugs for some populations, including veterans and federal prisoners, but they represent only a small fraction of the nation’s drug market.

“The frustration that the U.S. pays much higher prices for drugs has been a persistent theme of this administration,” said Peter Bach, the director of the Memorial Sloan Kettering Center for Health Policy and Outcomes, in an email. “We will have to see what is ordered to understand what could actually be implemented by executive order. The scope will have to be pretty limited in that the government itself does very little purchasing of drugs. It is all done through intermediaries that we pay for the service.”

The Department of Health and Human Services published a white paper of possible drug pricing policies last year, and has begun rolling out regulations to help enact portions of it. Congress is also seriously considering a handful of measures related to drug pricing, some of which may become law this year.

A bill introduced by Senator Rick Scott, a Republican from Florida, has not advanced to a committee hearing, but comes the closest to what the president described Friday. Mr. Scott’s bill would link a drug’s approval by the Food and Drug Administration to a requirement that the drug’s retail list price in the United States be no higher than the lowest price charged in Canada, France, Britain, Japan or Germany.