Iran's new anti-money laundering bill, as passed, reportedly has a number of shortcomings, but none so serious as the deletion of the provision that imposes an absolute ban on changing the identity on individuals and entities that conduct financial transactions. This means that anyone, or any entity, that is subject to sanctions may have their identities altered, so as to deceive the recipients, and all the banks handling the transactions.
What this is is a loophole that aids and abets money laundering and terrorist financing. Iranian bankers can now conceal the identity of account holders, meaning that they can knowingly change the name of a sanctioned client, and not violate the AML laws.
If you needed a reason to block ALL transactions that originated in Iran, irrespective of how clean the sender was, here are the necessary legal grounds to support that action.