Government officials are reportedly undecided as to whether states can implement partial Medicaid expansions, according to reports.

Centers for Medicare & Medicaid Services official Cindy Mann said CMS is “still considering” if it will allow states to expand Medicaid eligibility to adults with incomes less than 133% of the federal poverty level. Mann, CMS’ director for Medicaid and CHIP Services, sidestepped that question at a regional forum CMS organized to layout implementation procedures, the Bureau of National Affairs reported.

State lawmakers and state Medicaid directors have been pushing CMS to clarify how many parts of the Affordable Care Act’s Medicaid expansion will be optional for states taking advantage of the law.

Mann said last week that states are free to participate in the ACA’s massive Medicaid expansion, and then opt out if should the program become too costly.