Acting Attorney General Todd Blanche signed an order reclassifying state-licensed medical marijuana as a less-dangerous drug on Thursday (April 23), marking a major policy shift sought by cannabis activists arguing that it never should've been treated like heroin by the federal government, the Associated Press reports.

The order doesn't legalize marijuana for medical or recreational use under federal law, however, does change how it's regulated, shifting licensed medical marijuana from Schedule I to Schedule III, while also allowing licensed medical marijuana operators a major tax break, as well as easing barriers in connection with cannabis research. Schedule I drugs are designated for those without medical use and deemed to have high potential for abuse.

President Donald Trump had previously ordered his administration to work on reclassifying marijuana in December and seemed to express frustration that the process was taking so long when he signed an unrelated executive order about psychedelics on Saturday (April 18). Blanche said the Department of Justice was “delivering on President Trump’s promise” to expand access to medical marijuana treatment options for Americans' after signing the order on Thursday.

“This rescheduling action allows for research on the safety and efficacy of this substance, ultimately providing patients with better care and doctors with more reliable information,” he said in a statement obtained by the Associated Press.

The action largely legitimizes medical marijuana programs in 40 states that have implemented them and sets up an expedited system for state-licensed medicinal marijuana producers and distributors to register with the U.S. Drug Enforcement Administration. Additionally, cannabis researchers won't be penalized for obtaining state-licensed marijuana or marijuana-derived products in connection with their studies, while marijuana companies will be permitted to deduct business expenses on federal taxes for the first time.

All marijuana-derived medicine approved by the U.S. Food and Drug Administration will be listed as a Schedule III drug moving forward. The order is the latest shift from the longstanding Marijuana Tax Act of 1937 as nearly all U.S. states have approved cannabis in some form, with more than two dozen authorizing adult recreational marijuana use, 40 implementing medical marijuana systems and eight more allowing low-THC cannabis or CBD oil for medical use.

Idaho and Kansas are the only two remaining states that have outright banned marijuana.