Secretary of Health and Human Services Louis W. Sullivan yesterday emphatically rejected national health insurance as an option he will consider in developing administration proposals on extending coverage to the uninsured and reducing health care costs.

He said any recommendation he sends to President Bush will be based on the principle that "the present private/public health system should be the primary means" of delivering health care to all Americans, including 31 million with no insurance.

"We do not want to rush in with unproven remedies which may create more problems than they solve," Sullivan said. Proponents of "a radical revamping of our health care system -- suggesting nationalized medicine -- are mistaken."

Sullivan also dismissed suggestions that the United States copy the Canadian system, in which provincial governments finance health care, saying there are "long waiting lists for critical procedures, and de facto rationing."

Bush announced in his State of the Union address last January that Sullivan would give him recommendations on how to deal with the soaring costs of health care and the people who cannot pay for it because they have no health insurance. Sullivan's remarks ended any possibility he would propose an all-government insurance system in place of the current one, which consists of group health insurance policies furnished by employers, privately purchased policies, and government programs for the poor (Medicaid) and the aged (Medicare).

A succession of witnesses at a Senate hearing yesterday argued in favor of national health insurance because the health care system is on the verge of "collapse" under the burden of treating uninsured patients.

But Sullivan, speaking to the Atlanta Business Roundtable, said that while it is important that private insurers offer a better "array of products that will meet individual needs" and that the government help people "who need extra help," the nation's health care "must remain a free market system."

Rejecting proposals to require employers to provide health insurance to their workers, Sullivan said that it would be "dangerous" to impose "overly burdensome mandates on business" lest they "retard economic growth and constrict employment opportunities."

In his speech, Sullivan did not rule out specially targeted efforts known to have been discussed in the administration, including the expansion of Medicaid to cover more of the poor and near-poor, or a system of tax credits for purchasing private insurance.

Another option would involve the insurance industry offering less-expensive group policies to small businesses, which usually are charged more per worker because they have fewer employees to share the risk.

Rep. Fortney Pete Stark (D-Calif.), who has proposed a 4 percent tax on income to pay for a national health care and long-term care plan, said Sullivan is "off base. It's sad to see him have to be pushed around" by the administration and forced to endorse "free enterprise in health care when it isn't doing the job."

Stark added, "In this country we ration health care to the poor by money. The rich get health care and the poor don't. It's worst for poor blacks."

But Donald White, spokesman for the Health Insurance Association of America, which represents firms providing health insurance, said, "We are strongly supportive of the secretary's principles and we look forward to working with him to provide health insurance coverage for more than 31 million uninsured."

Sullivan said improving health care and cutting costs also involves changes in life styles, including "more personal and family responsibility for physical well-being."

"Health insurance," he said, "will not reduce infant mortality for mothers who smoke, drink or abuse drugs during pregnancy" or "prevent cirrhosis of the liver for those who abuse alcohol."