ST. PAUL — 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.”