Washington ? Health insurance companies proposed a $300 billion plan Monday aimed at getting coverage for all uninsured children in three years and for most adults within 10.

The plan includes tax breaks for the working poor and increased government spending by the government for Medicaid and the State Children’s Health Insurance Program.

“This bold program would expand coverage to tens of millions within a framework that is fiscally sound and promotes individual responsibility,” said J. Grover Thomas Jr., board chairman of America’s Health Insurance Plans.

The largest of the tax breaks would go for universal health accounts. Individuals could set aside up to $2,000 a year and families up to $4,000 and use the money to pay for any type of health insurance, not just plans that require patients to pay significant upfront costs.

The insurers also called for giving low-income families a tax credit worth up to $500 when they secure health insurance for their children. They said their proposal would go a long way toward providing basic coverage to more than 40 million uninsured.

The trade group made no recommendations as to how the government should pay the bill of $300 billion over 10 years, but it noted that expanding coverage to the uninsured would bring significant savings to the insured. That’s because the insured subsidize much of the health care provided to the uninsured in the form of higher monthly premiums.

Health and Human Services Secretary Mike Leavitt said Monday that he had not seen the insurers’ proposal, but he did sense there were opportunities to expand insurance coverage next year that lawmakers from both parties could back.

Lawmakers from both parties have said reauthorizing the children’s health program next year would be a priority, and many have expressed hope that the program would be expanded.

The American Medical Assn., which represents physicians, said it welcomed the plan.

“Clearly, current programs to cover the uninsured are insufficient and more must be done,” said Dr. Ardis D. Hoven, an AMA board member.

The expansion of Medicaid, a state-federal partnership, to all people at 100 percent of poverty would help about 12 million people become insured. The universal health accounts would help about 25 million people afford insurance, the insurance group said.