WASHINGTON: Washington’s medical marijuana system is “not tenable” in light of new guidance from the U.S. Justice Department about its pot-related enforcement priorities, the chief federal prosecutors in the state said Thursday.

The warning came after the agency said it will allow the states of Washington and Colorado to move forward with plans to tax and regulate recreational marijuana sales.

In written statements, U.S. Attorney Jenny Durkan in Seattle and U.S. Attorney Michael Ormsby in Spokane promised the feds won’t hesitate to go after people operating outside the legal framework set up by Washington voters last fall.

The state legalized medical use of marijuana in 1998 but never offered many options for how patients are supposed to obtain the pot. They can grow it themselves or allow someone to grow it for them, but medical marijuana dispensaries are not allowed under state law.

Nevertheless, such dispensaries have proliferated — with no oversight by state government or controls on where the marijuana comes from or where it goes. Federal authorities have raided some they deem to be fronts for criminal activity.

“The continued operation and proliferation of unregulated, for-profit entities outside of the state’s regulatory and licensing scheme is not tenable and violates both state and federal law,” the nearly identical statements from the prosecutors said. “While our resources are limited, we will continue to enforce federal law in this arena.”

Washington and Colorado last fall became the first states in the country to legalize the possession of marijuana by adults over 21. The votes also called for systems of state-licensed pot growers, processors and retail stores _ prompting much hand-wringing about whether the federal government would sue to block the schemes from taking effect, on the grounds they conflicted with the federal ban on marijuana.

But Thursday, the Justice Department gave states the green light to license and tax pot sales  — as long as the states ensure that certain federal priorities, such as keeping marijuana away from kids and the black market, aren’t jeopardized.

“The department guidance is premised on the expectation that the state will implement strong and effective regulatory and enforcement systems,” Durkan said.

The announcement was good news for the activists and officials who have been working on the state’s recreational pot law. Gov. Jay Inslee and Attorney General Bob Ferguson called it an endorsement of the careful approach Washington has taken toward legalization.