The US Department of Justice has officially reclassified cannabis as less dangerous, marking a major shift in the country's drug policy.

Acting Attorney General Todd Blanche on Thursday changed the classifications of products containing marijuana that are covered by the Food and Drug Administration or that have received a state medical-marijuana licence. They will move from a Schedule I narcotic like heroin to a Schedule III drug - on par with Tylenol with codeine.

He also called a hearing to consider reclassifying all marijuana.

President Donald Trump directed his administration last year to begin the reclassification process, in order to increase access and research of the drug.

Marijuana remains illegal at the federal level. Despite the federal ban, most US states have legalised the medical or recreational use of marijuana, and many have shops where it can be purchased legally.

"The Department of Justice is delivering on President Trump's promise to expand Americans' access to medical treatment options," Blanche said in a statement announcing the change. "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."

According to the announcement, Blanche also ordered that a hearing be held in June as part of a rule-making process to reclassify all marijuana more broadly.

Once the rule change is published in the Federal Register, it has 30 days until it takes effect. During that time, it can be legally challenged - which is expected - and be blocked from being implemented for months or even years.

Blanche's order comes five days after Trump signed an executive order intended to boost access to psychedelic drugs for medical treatment.

Since 1970, the US has claissified marijuana as a Schedule I controlled substance, meaning it possesses a "high potential for abuse" and there was "no currently accepted medical use".

Since then, many states have enacted their own laws to loosen restrictions on marijuana, which started with places like California allowing it to be used for medical purposes. That has created a patchwork of regulations and enforcement on cannabis, and also a headache for marijuana businesses who still have to follow federal tax and banking laws.

President Joe Biden's administration initiated a review of marijuana's classification in 2022 and about a year later the US health department recommended a change for the first time. In 2024, the Drug Enforcement Administration (DEA) requested hearings, but then those hearings were indefinitely postponed.

Trump's change is mostly "symbolic", said Morgan Fox of the National Organization for the Reform of Marijuana Laws (Norml).

More than two-thirds of Americans support full legalisation of cannabis, according to Fox, who said changing the classification will open the door to policymakers seriously considering lifting restrictions on it.

"Moving it out of that classification allows us to have policy conversations that don't start and end with that definition," Fox said. "Lots of policymakers continue to fall back on that, and really won't even discuss the issue as long as cannabis is Schedule I."

Fox, though, said that his group and other campaigners will continue to push for full federal legalisation.

"The real solution to the issue is to de-schedule cannabis at the federal level, not just move to Schedule III, and then start changing the laws in regulatory ways that provide guidance, so we can get a little bit of uniformity," said Fox.