WASHINGTON (WCMH) – The Drug Enforcement Administration said Thursday that it will not approve a proposal for the use of marijuana for medical purposes.

Marijuana is currently classified as a Schedule I drug, along with heroin and LSD. Other drugs like oxycodone and methamphetamine are classified as Schedule II, which allows for medical use.

The schedule I classification means that the agency has found the substance has a high potential for abuse, there is no currently accepted medical use and there is a lack of accepted safety for use under medical supervision.

The DEA says the medical value of the drug has not been proven scientifically, according to CNN.

The ruling comes as 25 states plus the District of Columbus have passed laws legalizing some form of medical use.

The DEA did make one policy change, however. The number of places allowed to grow marijuana for research purposes will be expanded.

Currently, only one federally licensed program can legally grow marijuana for study. That is the University of Mississippi.