State Medicaid directors are opposing a Republican Obamacare overhaul bill that would greatly restructure the federal-state healthcare program for the poor in their jurisdictions.

The National Association of Medicaid Directors said Thursday that the bill would impose significant challenges to states, chiefly that they would shoulder too much risk under the legislation. The group is the latest stakeholder to oppose the measure, joining doctors, insurer and hospital groups skeptical of what is considered by Republicans their last chance to overhaul Obamacare.

The directors say the bill doesn't give states enough time to set up new programs. The legislation led by Sens. Bill Cassidy, R-La., and Lindsey Graham, R-S.C., would give Obamacare funding to states through block grants.

It would keep Obamacare in place until 2020, at which time state-run programs for the individual insurance market and Medicaid would be implemented. The association says that is nowhere near enough time.

"The scope of this work, and the resources required to support state planning and implementation activities, cannot be overstated," it said. "States will need to develop overall strategies, invest in infrastructure development, systems changes, provider and managed care plan contracting, and perform a host of other activities."

It added the "vast majority" of states couldn't do that within two years.

The association was also concerned that there won't be a full analysis of the legislation by the nonpartisan Congressional Budget Office. The CBO has said it will provide a preliminary analysis early next week on the bill's impact on the deficit, but a full analysis of premiums and insurance coverage could take weeks.

Senate Majority Leader Mitch McConnell intends to hold a vote next week on the legislation, which still lacks enough support for final passage. Republicans have until Sept. 30 to pass the bill with only 51 votes, as the instructions to use a budget tool called reconciliation expire.

"With only a few legislative days left for the entire process to conclude, there clearly is not a sufficient time for policymakers, governors, Medicaid directors or other critical stakeholders to engage in the thoughtful deliberation necessary to ensure successful long-term reforms," the association said.