The Obama administration has decided marijuana will remain on the list of most-dangerous drugs, fully rebuffing growing support across the country for broad legalization, but said it will allow more research into its medical uses.

The decision to expand research into marijuana's medical potential could pave the way for the drug to be moved to a lesser category. Heroin, peyote and marijuana, among others, are considered Schedule I drugs because they have no medical application; cocaine and opiates, for example, have medical uses and, while still illegal for recreational use, are designated Schedule II drugs.

The Drug Enforcement Administration said the agency's decision came after a lengthy review and consultation with the Health and Human Services Department, which said marijuana "has a high potential for abuse" and "no accepted medical use." The decision means that pot will remain illegal for any purpose under federal law, despite laws in 25 states and District of Columbia that have legalized pot for either medicinal or recreational use.