California could face “significant legal risk” if it engaged in interstate cannabis sales, Attorney General Rob Bonta’s office said Wednesday in an opinion that douses immediate industry hopes of opening new markets for the Golden State’s oversupply of marijuana.

In a 36-page opinion, Deputy Attorney General Karim Kentfield wrote that selling California cannabis in other legalized states might be challenged under the federal Controlled Substances Act. And, Kentfield added, there’s no guarantee federal prosecutors wouldn’t pursue charges against state officials.