BOISE, Idaho — Federal officials on Thursday rejected one of Idaho's requests for a waiver for Medicaid expansion, causing Gov. Brad Little and other Republican leaders to say the federal government "pulled the rug out from under us."

But Little said the state is already taking steps to submit additional information to get the waiver approved.

The U.S. Department of Health and Human Services in a letter to Idaho Department of Insurance Director Dean Cameron said the state's application didn't provide enough information for the department to evaluate the waiver.

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The waiver would allow those earning between 100% and 133% of the federal poverty level to stay on the state's health insurance exchange, called Your Health Idaho. Backers said it would save the state millions of dollars, while those opposed said it would leave poor residents unable to pay medical bills.

"We have determined that Idaho's application does not meet all the requirements and is incomplete," wrote Randy Pate, deputy administrator of the department's Centers for Medicare and Medicaid Services.

The agency also said that even if Idaho revised its application, the federal agency couldn't approve the waiver because it wouldn't comply with guardrails in the federal law. The agency noted that Idaho's application didn't offer any information supporting a conclusion that the "waiver would not increase the federal deficit."

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Little and Republican leaders said they were disappointed and surprised by the federal agency's assessment.

"For months, state agencies worked closely with the federal agencies on the purpose and goals of the waiver application," they said in a joint statement. "We shared multiple strategies and considerations about how Idaho would approach the cost neutrality portion of the application. At no time during those conversations did the federal government indicate Idaho's approach to the budget neutrality guardrail would be insufficient for consideration."

Voters authorized Medicaid expansion with an initiative in November that passed with 61% of the vote after years of inaction by the Idaho Legislature. The federal government would pay 90% of the estimated $400 million cost to cover about 90,000 low-income residents. But Idaho lawmakers earlier this year added a handful of restrictions to the law, each requiring waivers from the federal government

"This is what happens when angry legislators try to steer working Idahoans onto plans that offer less comprehensive coverage for higher costs and greater out-of-pocket expenses," said Rebecca Schroeder, executive director of Reclaim Idaho, the group behind the voter-approved Medicaid expansion initiative.

Those other waivers, including a work requirement that would kick people off Medicaid if they don't find employment, must still go through a public comment period before Idaho officials also seek waivers for them from the federal government.

"Idahoans have asked us to implement Medicaid Expansion as-is but Republican legislators are determined to waste taxpayer dollars on restrictions," said the Joint Democratic Caucus Leadership in a statement. "It has become increasingly clear that these legislators do not advocate for the people and are only interested in their own power."