ATLANTA - Georgia's insurance commissioner will keep the state out of the first phase of a new federal health care law that would offer subsidized premiums to people with health problems.

In a letter obtained Monday by The Associated Press, Republican John Oxendine said Georgia should not take part in the creation of an insurance pool, backed by $5 billion in federal money, that would help high-risk people who have been uninsured for at least six months.

Federal health officials said they will run a coverage program in the state if Georgia doesn't take part.

In the letter to U.S. Health and Human Services Secretary Kathleen Sebelius, Oxendine said he has "no confidence" the program will not be a burden on Georgia taxpayers. The program is funded by all federal money, but Oxendine said he worries that down the road the state will have to foot the bill.

"I'm not going to subject Georgia taxpayers and the Georgia treasury to something that's going to be a burden on them," Oxendine said in an interview.

Oxendine, who is running for governor, noted 18 states have sued to overturn the federal health care law. Georgia's Democratic Attorney General Thurbert Baker has refused calls from GOP Gov. Sonny Perdue to join the lawsuit. Perdue has said he will select an outside lawyer to mount a legal challenge on Georgia's behalf.

"The very constitutionality of this law is in serious question," Oxendine said.

The state could still override Oxendine and push through legislation to participate in the program, but the chances of that happening in the Republican-controlled General Assembly are slim.

Sebelius gave states an April 30 deadline to say whether they would participate. HHS is planning a federal backup program - available nationally - to serve residents of states that won't or can't participate.

Nicholas Papas, spokesman for the U.S. Department of Health and Human Services, could not say whether any other states have declined to participate. Oxendine said he was unaware of any others who had said no.

States who participate could tailor the program for their residents, within federal guidelines. Some could piggyback off existing state programs. Others could contract with insurance carriers in their states to provide the high-risk coverage.

Starting this summer, the new high risk insurance program would help people too sick to get health coverage from a commercial carrier. Individuals could sign up for coverage through a risk pool in their own state, if available, or join the national plan.

Most states currently operate high risk insurance pools, but only about 200,000 people have been able to get coverage, because premiums are generally very high.

Federal help for high risk pools is one of most significant immediate benefits of President Barack Obama's signature health care law, which eventually will provide coverage to most of the uninsured. However, since the big coverage expansion doesn't come until 2014, the insurance pool was created to offer temporary assistance to vulnerable people.

Under the health care legislation, the federal government will pump money into the high risk pools, bringing down premiums so more people can sign up. Government economic experts estimate that 375,000 uninsured people with health problems would gain coverage this year through the program.

But the same experts - analysts for Medicare - also question whether the $5 billion allocated is enough to fund the program until 2014. The projected the funds will run out by 2012, leaving beneficiaries - and lawmakers - in a quandary.

Administration officials have said, if necessary, they will seek more money from Congress.