The passage of state laws decriminalizing the possession of small amounts of marijuana could put pressure on Congress to reschedule the drug, President Obama said in a recent interview with Shane Smith, founder of VICE, the alternative media organization.

The criminalization, he says, has “not just had a terrible effect” on many communities, particularly those of color, but it has also proven costly for states. With politicians increasingly warming to the idea of decriminalization, he added, more and more states may join. In turn, that may encourage Congress to move the drug from the Drug Enforcement Agency’s harshest grouping of controlled substances — Schedule 1 — to the second of five such categories.

“We may be able to make some progress on the decriminalization side,” Obama says around the 16:30 mark in the video embedded above, published Monday afternoon. “At a certain point, if enough states end up decriminalizing, then Congress may then reschedule marijuana.”

Rescheduling the drug would have consequences both symbolic and real. It would represent a major success for advocates of the drug, removing it from a category of drugs which the DEA deems to have “no currently accepted medical use and a high potential for abuse.” A comprehensive and bipartisan federal medical marijuana proposal introduced last week would reschedule marijuana, but only in states where it has been legalized for medicinal uses.

So far, 19 states and D.C. have decriminalized the possession of small amounts of marijuana, while others are considering enacting similar changes. The New Mexico Senate, for example, approved such a bill over the weekend.

As in past interviews, President Obama’s comments on marijuana were measured:

But I always say to folks: You know, legalization or decriminalization is not a panacea. Do you feel the same way about meth? Do we feel the same way about coke? How about crack? How about heroin? And there is a legitimate I think concern about the overall effects this has on society and particularly vulnerable parts of our society. Substance abuse generally — legal and illegal substances — is a problem. Locking somebody up for 20 years is probably not the best strategy and that’s something that we have to rethink as a society as a whole.

In the interview, Smith describes marijuana legalization as the issue that VICE, which is often credited for attracting the coveted millennial audience, gets asked most frequently about.

“Let’s put it in perspective,” Obama said in response. “Young people, I understand this is important to you, but you should be thinking about climate change, the economy, jobs, war and peace, maybe way at the bottom you should be thinking about marijuana. I’d separate out the issue of the criminalization of marijuana from encouraging its use.”

But advocates take issue with that characterization.

“The president is right that as voters force more and more changes to state marijuana laws, national policymakers will have no choice but to catch up,” Tom Angell, chairman of Marijuana Majority said in a statement. “But he should think again about how important this issue is. On average, there’s a marijuana possession arrest in the U.S. about every minute. Billions of dollars are wasted on enforcing prohibition laws that don’t stop anyone from using marijuana but do ruin people’s lives with damaging criminal records.”

The president should use his executive authority, Angell and other advocates argue. The VICE blog post in which the video was embedded was published at 4:20 p.m., a number of great significance to marijuana fans and advocates.