Marijuana and its key components should be formally rescheduled under international drug treaties, according to global health experts at the United Nations.

The World Health Organization (WHO) is recommending that whole-plant marijuana and cannabis resin be removed from Schedule IV, the most restrictive category of a 1961 drug convention adopted by countries from around the world.

According to an unreleased WHO document circulated by cannabis reform advocates, the organization also want delta-9-tetrahydrocannabinol (THC) and its isomers to be completely removed from a separate 1971 drug treaty and instead added to Schedule I of the 1961 convention.

Marijuana and cannabis resin are currently dual-designated in Schedules I and IV, with the latter reserved for those substances that are seen as particularly harmful with limited medical benefits. This differs from the U.S., where under the federal system Schedule I is where the supposedly most dangerous and restricted drugs – like marijuana, heroin, and LSD – are classified. Marijuana and cannabis resin would remain in Schedule I of the 1961 treaty.

While cannabidiol and CBD-focused preparations are not scheduled under international conventions, the WHO also wants to make clear that CBD containing no more than 0.2 percent THC are “not under international control” at all.

Cannabis extracts and tinctures would be removed from Schedule I of the 1961 treaty under the recommendations, and compounded pharmaceutical preparations containing THC would be placed in Schedule III of that convention.

The practical effects of the proposed changes are limited insofar as countries would still not be in strict compliance with international law by legalizing marijuana. Politically, however, it is a very significant move.

The WHO’s recommendations, if adopted, would represent a formal admission that the world’s governing bodies have effectively been wrong about marijuana’s harms and therapeutic benefits for decades. This comes at a time when a growing number of countries are already moving to revise their cannabis policies. Such a shift at the UN level could encourage other nations to reform their prohibition laws – even though legalization for non-medical or non-scientific reasons would still technically violate the global treaties.

“The placement of cannabis in the 1961 treaty, in the absence of scientific evidence, was a terrible injustice,” said Michael Krawitz, a U.S. Air Force veteran and legalization advocate who has pushed for international reforms. “Today the World Health Organization has gone a long way towards setting the record straight. It is time for us all to support the World Health Organization’s recommendations and ensure politics don’t trump science.”

The proposals are expected to go before the UN’s Commission on Narcotic Drugs by March, where 53 member nations will vote on whether to accept or reject them.

Countries that have historically opposed drug policy reforms, such as Russia and China, are expected to reject the change in cannabis’ classification.

The proposals are likely to be backed by countries that have are already legalized marijuana, like Canada and Uruguay, or where medical cannabis is permitted, as in a number of European and South American nations.

It is less clear how the U.S. will vote. Historically, the U.S. has pressured other nations not to reform their own marijuana policies, but legalization in a growing number of states in recent years makes that increasingly untenable.

The Trump administration last year revoked Obama-era prosecutorial guidance that generally urged non-intervention with state-level marijuana laws. But the president has also voiced support for allowing states to set their own cannabis policies. Trump’s pick for attorney general, William Barr, said during his confirmation hearing that he would not “go after” companies reliant on the now-rescinded cannabis guidance.

So, it is uncertain how the Trump administration will direct its UN representative to act on the proposed changes to marijuana’s status under international law.

The WHO’s new cannabis rescheduling recommendations come in the form of a letter, dated January 24, from the Tedros Adhanom Ghebreyesus, the body’s director general, to UN Secretary-General Antonio Guterres.

Guterres was Portugal’s prime minister when the country enacted a policy of decriminalizing drug possession, a move he touted in a speech to the UN’s Commission on Narcotics Drugs last year.