Creation of new SAP ME System Rule without IDAT

Hi,

We all know that to create a new System rule in SAP ME we need to do the same using an IDAT XML file. Then we need to do a plant data initial load and the then the new system rules can be visible in the System Rule Maintenance activity. I have one question regarding the same. Can we create a new system rule for a certain site without using the IDAT XML file or rather is there a different way of creating a new system rule in SAP ME. Please let me know.

Thanks

Anirban