Gov. Mark Dayton's plan to expand the state's Medicaid rolls by 95,000 people has been approved by federal authorities, his office said Thursday.

The move, which begins March 1, will provide health insurance to 12,000 low-income adults who previously were uninsured, and broader coverage at lower cost to another 83,000 who received care under two state-funded programs, MinnesotaCare and General Assistance Medical Care.

The savings from reducing caseloads in the two state programs will offset the additional state cost in Medicaid, state budget officials have said. Medicaid, known in Minnesota as Medical Assistance, is funded jointly by the state and federal governments.

Legislative Republicans have criticized the move, arguing that Minnesota might get stuck with the bill if budget problems in Washington eventually curtail the federal contribution.

But Dayton had the authority to order the expansion under a compromise brokered last spring between the Legislature and then-Gov. Tim Pawlenty.