Delete PO line

Hi All

In the Standard Purchase Order the end user able to Delete PO line even though it has been resubmitted for approval (Not Approved).  User Can un-reserve the PO once it has rejected then the line can be deleted at all.

unlike the Purchase Requisition, once it has been submitted for approval you can't delete any line at all unless you cancel the line.

what is the possibility of making the PO behavior same as Purchase requisition.  i.e. don't allow to delete line from PO in case of submitted for approval at least once.

BR