How to prevent purchase order entry where no supplier/item relationship exists

I have looked through many of the responses to similar questions however I have not seen a response to the exact issue that we are trying to resolve.  We have to certify every item with every vendor that we purchase from, therefore we need to be able to manage our relationships at the supplier/item level.  I cannot find a way to prevent our purchasing department from placing an order with a vendor that has never provided us with that particular product before.

If we have the Supplier Analysis processing option turned on and the have the default setting for supplier/item relationship creation to add a certification status with a special handling code = 1 will that cause a hard error upon initial creation during order entry?  Are there other options for addressing this?