Top state lawmakers are trying to work out a system allowing Iowa residents to start buying medical marijuana oils and pills in Minnesota, a novel arrangement that could raise issues with the federal government.

Iowa could join more than two dozen states with medical marijuana programs under a bill awaiting Gov. Terry Branstad's signature. That legislation would expand a limited 2014 law, allowing more patients to buy the low-dose medication from in-state dispensaries by December 2018.

But in the meantime, Iowa residents could look to Minnesota. A provision of the bill specifically references that state as a potential source of medication and directs Iowa regulators to contract with Minnesota's two manufacturers of medical marijuana.

It's the first half of an arrangement being worked out between Iowa House Speaker Linda Upmeyer and Minnesota House Speaker Kurt Daudt, friends who first explored the idea last year until the push to expand Iowa's medical marijuana law fizzled out. Both lawmakers confirmed their discussions to The Associated Press this week.

Upmeyer said Minnesota could offer immediate relief to sick Iowans while the state works to set up its program over the next 18 months. Minnesota may even serve as a permanent back-up in case the state can't secure its own manufacturer, a prospect she and others have feared.

"It's providing access to Iowans and doing it as quickly as we can," Upmeyer said. "I just want to be sure if we have a tough time finding a grower, we have another source available. It all just fits together."

Iowa Gov. Terry Branstad has been noncommittal on the legislation since it hit his desk earlier this month. He is expected to act on the bill before leaving office to become President Donald Trump's ambassador to China, pending the U.S. Senate's confirmation.

While several states with medical marijuana laws recognize cardholders from other states, sending residents across the border to buy their supply would be a new arrangement if both sides move ahead. The nearest of Minnesota's eight dispensaries to Iowa is in Rochester, a roughly three-hour drive from Des Moines.

That arrangement could raise federal concerns. Despite its legal status in nearly 30 states, the federal government still considers medical marijuana a Schedule I drug that can't be moved across state lines. And fears of a federal crackdown on states with medical marijuana laws have increased under Attorney General Jeff Sessions, who has repeatedly expressed his disapproval of the drug.

Upmeyer said she's trying to meet with Sessions' office to get greater clarity on how the federal government might treat Iowa's arrangement.

Medical marijuana sales began in Minnesota in July 2015. If Branstad signs the bill, Iowa patients with a doctor's certification could start registering immediately.

Both states would have restrictive programs that ban the use of the plant form and limit the availability of marijuana oils and pills to patients with just a handful of severe conditions. Iowa's law goes farther by limiting the potency of the oils that can be sold.

It's unclear how many Iowa patients might take advantage of being able to buy their supply in Minnesota, but Daudt said any patients from Iowa could help manufacturers in Minnesota, where the tight restrictions have led to lackluster patient enrollment, high medication costs and huge financial losses for both companies. Though Daudt voted against the 2014 legislation that created Minnesota's program, he said he's open to the arrangement.

"One of the problems that we have had here is that the manufacturers ... have a limited number of customers, and it may become difficult to sustain their business," Daudt said Thursday. "It may be helpful to our manufactures and ultimately to our jobs and economy here in Minnesota. I think it could be a mutually beneficial thing."

It would require specific legislation allowing out-of-state residents to buy their medication in Minnesota, a measure that could be tucked into the massive budget lawmakers are working to finalize. Daudt said lobbyists for Minnesota's two manufacturers, Minnesota Medical Solutions and LeafLine Labs, and medical marijuana advocacy groups have been working on crafting the language.

Minnesota's regulators haven't been involved in the discussions, nor has Democratic Gov. Mark Dayton, who was never a strong backer of Minnesota's law. Michelle Larson, who runs Minnesota's Office of Medical Cannabis, said they would need to figure out how to handle a new crop of patients from a different state in their patient registry system. And the prospect of Iowa residents facing problems for bringing Schedule I medication across state lines worried her.

"We'd certainly want to make sure people were aware of the risk," Larson said.