Attorney General Jeff Sessions hinted that the Department of Justice might begin more aggressive enforcement of federal laws against recreational marijuana, even in states that have legalized it.

Speaking at the National Association of Attorneys General’s annual winter meeting on Tuesday, Sessions said that the agency might enforce laws in eight states and Washington, D.C., that have legalized recreational marijuana.

“States, they can pass the laws they choose,” he said. “I would just say, it does remain a violation of federal law to distribute marijuana throughout any place in the United States, whether a state legalizes it or not.”

Sessions, who has long opposed marijuana legalization, reiterated that view in response to a question on drug policy.

“I’m not sure we’re going to be a better, healthier nation if we’re going to have marijuana being sold at every corner grocery store,” he said.

Sessions’ comments echoed White House spokesman Sean Spicer, who predicted harsher prosecution of marijuana under the Trump Administration at a press briefing Thursday.

“I do believe you’ll see greater enforcement of it,” he said. Spicer clarified that Trump supports medical marijuana but “that’s very different than recreational use, which is something the Department of Justice will be further looking into.”

This would all mark a significant priority shift from the Obama Administration, which said in a 2013 memo that the federal government would generally not intervene in states that had legalized marijuana except in cases where the drug was being sold to minors, being sent across state lines or other specific infractions.

It’s also a break from Trump’s own remarks on the campaign trail.

In a TV interview in Colorado in July of 2016, Trump said that he would not use federal law enforcement to go after recreational marijuana in states where it is legal, saying that legalization is an issue for states to decide.

“I think it’s up to the states,” he said.

Such enforcement could prove unpopular. In a Quinnipiac poll of 1,323 voters nationwide conducted earlier this month, 71 percent of respondents said the federal government should not enforce federal laws against marijuana in states that have legalized it.