PNC Bank is closing the accounts of influential cannabis legalization group Marijuana Policy Project.

“They have notified us that they intend to close it,” MPP spokesman Mason Tvert told CNNMoney. “It’s because we accept contributions from businesses or individuals who are involved with state regulated marijuana businesses.”

While the group does not directly handle the cultivation, distribution or sale of cannabis, it does accept monetary donations from business that operate legally in cannabis states. MPP has banked with PNC for more than 20 years.

MPP Chief Operation Officer Nick Field told the Washington Post a PNC Bank representative told him in May the group’s accounts would be closed by July 7 due to an audit which revealed MPP received funding from cannabis businesses that directly handle the plant. The bank stated they cannot assume the risk of the accounts while cannabis is still illegal under federal law.