iSupplier: User restriction as per Supplier Site

Hi,

Is it possible in iSupplier to restrict users see data (PO) only the supplier and site combination he has access to?

e.g.

Supplier - A having sites X, Y

User1 has access to only site X and user2 has access only to Site Y.

So is it possible that user1 can see only POs with Supplier A and Site X in planning tab and not Supplier-A with site Y?

Similarly for user2

Thanks