(CNN) Kentucky Republican Gov. Matt Bevin has suspended dental and vision benefits for nearly 500,000 Medicaid recipients after a federal judge blocked his plan to overhaul the safety net program.

Bevin's administration was set to launch a massive reorganization of Medicaid benefits on July 1. The changes, which were approved by the Trump administration in January, included requiring certain beneficiaries to work and to pay premiums. The reorganization also would have changed dental and vision coverage for many low-income adults.

The effort was halted -- at least temporarily -- on Friday after US District Judge James Boasberg voided the federal approval and kicked the matter back to the Department of Health and Human Services for further review. Calling the agency's approval "arbitrary and capricious," Boasberg said HHS Secretary Alex Azar had neglected to analyze whether Kentucky's plan would cause recipients to lose their health insurance coverage.

Bevin administration officials quickly warned that the state would have "no choice but to make significant benefit reductions" to offset the increasing cost of Medicaid expansion. On Sunday, they announced that dental and vision coverage would end for about 460,000 recipients until the overhaul moves forward.

These low-income, working-age adults gained the benefits when the state expanded Medicaid under Obamacare in 2014. Bevin's overhaul would have ended this coverage and shifted recipients into My Rewards Accounts, where they could earn credits to pay for dental and vision services by completing various activities, such as getting a mammogram or completing job skills classes.

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