American Express is no longer allowing transactions to be processed at medical marijuana dispensaries nationwide, according to published reports.

A spokesperson told the LA Weekly that the company made the decision to not allow its credit cards to be accepted for medical marijuana because it is their "policy to adhere to the federal law in such matters."

The American Independent reported that Rep. Jared Polis (D-CO) plans to introduce legislation to clarify that banks can maintain normal business relationships with legal medical marijuana dispensaries, possibly as soon as this week.

“I haven’t seen it with other credit cards,” Aaron Smith, executive director of the National Cannabis Industry Association, said. “I don’t understand why they would turn their back on a $2 billion industry. It’s perplexing.”