WASHINGTON  President Obama’s campaign to cut health costs by $2 trillion over the next decade, announced with fanfare two weeks ago, may have hit another snag: the nation’s antitrust laws.

Antitrust lawyers say doctors, hospitals, insurance companies and drug makers will be running huge legal risks if they get together and agree on a strategy to hold down prices and reduce the growth of health spending.

Robert F. Leibenluft, a former official at the Federal Trade Commission, said, “Any agreement among competitors with regard to prices or price increases  even if they set a maximum  would raise legal concerns.”

Already, some leaders of the health care industry who appeared at the White House on May 11 say the president may have overstated their cost-control commitment. Three days after the gathering, hospital executives said that they had agreed to help save $2 trillion by gradually slowing the growth of health spending, but that they did not commit to cutting the growth rate by 1.5 percentage points each year for 10 years.