DENVER, Aug. 24 (UPI) -- Colorado Springs State Bank, the last bank in the state willing to do business openly with medical marijuana suppliers, has asked them to close their accounts. DENVER, Aug. 24 (UPI) -- Colorado Springs State Bank, the last bank in the state willing to do business openly with medical marijuana suppliers, has asked them to close their accounts.

Senior Vice President John Whitten said the bank's parent company, Herring Bank, does business in Oklahoma and Texas, both states where medical marijuana is not legal, The (Boulder) Daily Camera reported.

"There are unresolved issues with regulations, law enforcement and other agencies that need to get resolved before the industry can progress and become bankable," Whitten said.

A letter last week to operators of medical marijuana dispensaries asked them to shut down their accounts by the end of September, Whitten said.

Diane Czarkowski, one of the owners of Boulder Kind Care, said the dispensary, which now has an account at Colorado Springs State, has been through six other banks since it opened in October 2009. She said Kind Care is now talking to a local bank.