A day after touting "states' rights" in moving to lift an Obama Administration directive on transgender bathroom use in public schools, the Trump Administration signaled on Thursday that while it supports the legalization of medical marijuana, it might be ready to clamp down on states that have legalized personal marijuana use.

"I think there's a big difference between that (medical marijuana) and recreational marijuana," said White House Press Secretary Sean Spicer.

"I think when you see something like the opiod addiction crisis blossoming in so many states around this country, the last thing we should be doing is encouraging people," as Spicer suggested that Attorney General Jeff Sessions and the Justice Department would be looking at the issue.

"They are going to continue to enforce the laws on the books with respect to recreational marijuana," Spicer added.

One Republican in Congress quickly made clear his displeasure with that pronouncement.

"No. Not a federal issue," said Rep. Justin Amash (R-MI).

The explanation from the White House about recreational marijuana is directly at odds with what President Trump had said on the campaign trail - in early August of 2016, he did an interview with KUSA-TV in Denver, where Mr. Trump made clear he thought the states should be allowed to legalize pot.

"You think Colorado should be able to do what it’s doing?" reporter Brandon Rittiman asked the GOP nominee about the Colorado law that allows people 21 and over to legally have up to one ounce of marijuana.

"I think it’s up to the states, yeah. I’m a states person," Trump said. "I think it should be up to the states, absolutely."

In October of 2015, Trump was asked about marijuana at a rally in Nevada, where he said he was all for medical marijuana, and then addressed recreational use.

"And then I really believe you should leave it up to the states; it should be a state situation," Trump said.

Nevada was one of four states to approve recreational marijuana use in the 2016 elections, along with California, Maine and Massachusetts, joining Colorado and Washington State.

It's unclear how the Justice Department might shake things up in those states, in what would be a U-turn for President Trump on recreational marijuana use.

The reaction from those in the marijuana industry was expected, labeling the Spicer statements "disappointing."

"We have hoped and still hope that the federal government will respect states' rights in the same manner they have on several other issues," said Derek Peterson, the CEO of Terra Tech, a company that grows legal marijuana for sale.

"We have hoped and still hope that the federal government will respect states' rights in the same manner they have on several other issues," Peterson added.