Nevertheless, the president was joined on Thursday by a bipartisan group of lawmakers, including Senators Bill Cassidy, Republican of Louisiana, and Maggie Hassan, Democrat of New Hampshire. Senator Lamar Alexander, Republican of Tennessee, told Mr. Trump that he could expect to see legislation by July.
In the House, Representative Frank Pallone Jr., Democrat of New Jersey and the chairman of the Energy and Commerce Committee, released a joint statement with his Republican counterpart, Representative Greg Walden of Oregon, expressing their interest in collaborating on the issue. At the same time, House Democrats are preparing to introduce a bill that would target a Trump administration rule that expanded the use of short-term health care plans that provide cheap, limited coverage.
The billing issue is consistently popular with voters. A poll last year by the Kaiser Family Foundation found that 67 percent of Americans worry about unexpected medical bills, with 38 percent saying they were “very worried” about them. As House Democrats sought to protect the Affordable Care Act and attack Mr. Trump’s medical initiatives, the president said that the billing initiative he announced on Thursday could be a “better” solution than a health care law.
A senior administration official who spoke on the condition of anonymity later told reporters that the president had been inspired to act after participating in a round-table in January and hearing from people who were affected by the billing practices.
A bill meant to help medical patients will most likely set up a battle with insurance companies, hospitals and doctors, stakeholders that will be looking to avoid shouldering the burden if consumers end up seeing relief.
Nationwide, more than one in five visits to an in-network emergency room results in an out-of-network doctor’s bill, studies have found. Yale research released by the National Bureau of Economic Research in 2017 determined that a select group of emergency room doctors at particular hospitals were responsible for much of the surprise billing.
At about 15 percent of the hospitals, out-of-network rates were over 80 percent, the study found, a figure administration officials cited on Thursday.
“You have to come up with a solution,” Mr. Grogan said in March, “or bad things could happen because you’ll have policymaking being made by people that don’t understand the system nearly as well as you.”