WASHINGTON (AP) _ Leaders of the nation's counties expressed concern Monday that the Clinton health plan would leave them stuck with the bills for treating jail inmates and illegal immigrants.

But the National Association of Counties applauded other aspects of the plan, including the promise of universal access, a broad benefits package and a mandate on all employers to help pay for workers' coverage.

Counties spend $30 billion a year on health care for 40 million people. They operate public hospitals in big cities where the uninsured often turn for help in an emergency.

''We need this proposal because property taxes cannot continue to pay for our nation's health safety net,'' Monterey County, Calif., Supervisor Barbara Shipnuck said at a news conference.

The group released a list of 37 questions about the draft Clinton health plan.

Most Americans would get health coverage through big, new insurance- purchasing alliances set up in every state.

But the plan would exclude illegal aliens from the guarantee of coverage and would leave prisoners as the responsibility of ''the various prison systems,'' not the alliances.

Illegal aliens could still seek care at public clinics or emergency rooms, but they would not get health security cards and a guaranteed package of benefits.

''Solutions must be found to relieve local governments of this burden,'' Shipnuck said.

The counties said that as much as $11 billion is spent on health care in county jails, and more than 90 percent of that comes from county budgets.

The Clinton plan would designate ''essential community providers'' in inner cities and other poorly served areas that would get special payments from health plans for at least five years.

The plan would automatically designate school-based clinics as essential community providers, but not county public health facilities.

St. Louis County, Minn., Commissioner Marilyn Krueger said that was inequitable. ''All public hospitals and other county health facilities and programs'' should get the special designation, too, she said.