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WASHINGTON, Aug 29 (Reuters) - The Obama administration has decided not to sue Colorado and Washington over new laws that legalized recreational marijuana, allowing the two states to carry on their experiment as long as they follow new federal guidelines, a U.S. Justice Department official said on Thursday.
Attorney General Eric Holder informed the two states' governors of the decision in a telephone call, said the official, who spoke on condition of anonymity.
The Justice Department was sending a memorandum to federal prosecutors nationwide explaining new guidelines on when they should bring marijuana-related criminal charges, such as when children are involved, the official said.
The decisions end nearly a year of deliberation inside President Barack Obama's administration about how to react to the growing movement for relaxed U.S. marijuana laws.
Marijuana remains illegal and tightly controlled under federal law, even as the two states legalized recreational use. Nearly 20 other states, plus the District of Columbia, allow the use of medical marijuana.
Obama signaled he did not want a new crackdown, telling ABC News in December: "It does not make sense, from a prioritization point of view, for us to focus on recreational drug users in a state that has already said that's legal."
The Justice Department stopped short of giving users, sellers and related businesses guaranteed immunity. Instead, it said in the guidelines that it would limit prosecutions to eight specific areas.
The areas include distribution to minors, marijuana trafficking across state borders and growing marijuana on federal land.
The guidelines will apply nationwide, not just in Colorado and Washington, the official said. (Reporting by David Ingram; editing by Howard Goller, Jackie Frank and Cynthia Osterman)