States that expand their Medicaid coverage under the health care reform law could later drop the expansion if they choose, Cindy Mann, Medicaid director for the Centers for Medicare & Medicaid Services, said Monday.

"We made it clear that the program, the expansion for low-income adults, is voluntary for states," Mann said. She made the statement at the National Conference of State Legislatures meeting in Chicago.

"States can decide when to come in, if to come in and also, if a state does adopt the expansion and determines at a later time for whatever reason that it does not want to maintain the expansion, it can also decide, because it's a voluntary program, to drop the expansion," Mann said.

Whether states would have the flexibility to opt both in and out of the expansion is one of several key questions from governors who have not yet announced their decision on the issue. Pennsylvania Gov. Tom Corbett is among them.

According to Kaiser Health News, Mann's statement was the first indicating that states will be allowed to drop such new coverage if they choose.