President Donald Trump has reportedly lent his support to a U.S. senator from Colorado, promising to back legislation that “protects states’ rights” on legalized marijuana.

The president's decision would represent a split from U.S. Attorney General Jeff Sessions, who in January rescinded an Obama-era policy, known as "the Cole memo," that gave states more leeway over the federal government on marijuana policy.

The name refers to former Deputy Attorney General James Cole, whose memo explained the policy.

In a statement Friday, U.S. Sen. Cory Gardner, a Republican, said he’d received an assurance from the president on the states' rights' issue earlier this week.

“Since the campaign, President Trump has consistently supported states’ rights to decide for themselves how best to approach marijuana,” Gardner said. “Late Wednesday, I received a commitment from the President that the Department of Justice’s rescission of the Cole memo will not impact Colorado’s legal marijuana industry.

“Furthermore," Gardner added, "President Trump has assured me that he will support a federalism-based legislative solution to fix this states’ rights issue once and for all.”

U.S. Sen. Cory Gardner, R-Colo., addresses reporters, Jan. 22, 2018. (Associated Press)

White House Press Secretary Sarah Huckabee Sanders confirmed Gardner's account of the president's thinking -- but Sessions' reaction was not immediately known. According to The Los Angeles Times, Trump did not inform Sessions in advance of the change in policy.

Trump and Sessions have had moments of friction in their relationship for months, on issues unrelated to the legality of marijuana. For instance, Sessions, an early supporter of candidate Trump, has been sharply criticized by the president in recent months over his decision to recuse himself from an investigation into alleged Moscow meddling in the 2016 presidential election.

As for marijuana itself, during the presidential race Trump said states should be able to decide their own pot policies. "I'm a states person, it should be up to the states, absolutely," he told a television interviewer in Colorado that year.

However, a year earlier at CPAC (Conservative Political Action Conference) in Maryland, Trump had said he supported medical marijuana but called recreational pot "bad."

He singled out Colorado, the first state to allow recreational marijuana sales. "They've got a lot of problems going on right now in Colorado - some big problems," Trump said then.

When Trump selected Sessions, a former federal prosecutor and U.S. senator from Alabama, as his attorney general, marijuana supporters girded for a crackdown. But Gardner said Sessions had promised him he'd do nothing to interfere with Colorado's robust marijuana market.

Gardner said he was blindsided when Sessions made his announcement in January regarding pot prosecutions.

In retaliation, Gardner used his power as a senator to prevent consideration of any nominees for the Department of Justice — an extraordinary step for a senator against an administration run by another member of his own political party.

As recently as earlier this month, marijuana legalization advocates and industry leaders were continuing to brace for an administration crackdown and for fresh tensions with the Trump administration – even coaching those in the business how to handle federal raids – as top officials were anticipating “greater enforcement” on the horizon.

“It’s definitely an interesting time. We are nervous,” said Beth Collins, senior director of government relations with Americans for Safe Access (ASA).

Gardner and Justice officials have been in discussions for months to get the holds lifted. Gardner has met with Sessions and Deputy Attorney General Rod Rosenstein, the official overseeing the Russia probe who has been the target of Trump's ire.

In his Friday statement, Gardner said he had released some holds, but left others in place until he acquired “a full commitment that the guidelines of the Cole Memo would be respected.”

Meanwhile, legislation to protect states where marijuana is legal is still being drafted. Trump's backing is seen as key to getting a bill through Congress.

Fox News' Adam Shaw and Jake Gibson and the Associated Press contributed to this report.