diff --git a/addons/purchase/purchase.py b/addons/purchase/purchase.py
index 4a5b2567377..8cae5a1cf15 100644
--- a/addons/purchase/purchase.py
+++ b/addons/purchase/purchase.py
@@ -1114,6 +1114,9 @@ class procurement_order(osv.osv):
             If none match, returns then first warehouse of the company
         """
         # TODO refactor the domain once we implement the "parent_of" domain operator
+        # NOTE This method has been copied in the `purchase_requisition` module to ensure
+        #      retro-compatibility. This code duplication will be deleted in next stable version.
+        #      Do not forget to update both version in case of modification.
         company_id = (procurement.company_id or user_company).id
         domains = [
             [
diff --git a/addons/purchase_requisition/purchase_requisition.py b/addons/purchase_requisition/purchase_requisition.py
index c15d145a7cd..c1d80c7bf46 100644
--- a/addons/purchase_requisition/purchase_requisition.py
+++ b/addons/purchase_requisition/purchase_requisition.py
@@ -236,6 +236,35 @@ class procurement_order(osv.osv):
         'requisition_id': fields.many2one('purchase.requisition', 'Latest Requisition')
     }
 
+    def _get_warehouse(self, procurement, user_company):
+        """
+            Return the warehouse containing the procurment stock location (or one of it ancestors)
+            If none match, returns then first warehouse of the company
+        """
+        # NOTE This method is a copy of the one on the procurement.order defined in purchase
+        #      module. It's been copied to ensure it been always available, even if module
+        #      purchase is not up to date.
+        #      Do not forget to update both version in case of modification.
+        company_id = (procurement.company_id or user_company).id
+        domains = [
+            [
+                '&', ('company_id', '=', company_id),
+                '|', '&', ('lot_stock_id.parent_left', '<', procurement.location_id.parent_left),
+                          ('lot_stock_id.parent_right', '>', procurement.location_id.parent_right),
+                     ('lot_stock_id', '=', procurement.location_id.id)
+            ],
+            [('company_id', '=', company_id)]
+        ]
+
+        cr, uid = procurement._cr, procurement._uid
+        context = procurement._context
+        Warehouse = self.pool['stock.warehouse']
+        for domain in domains:
+            ids = Warehouse.search(cr, uid, domain, context=context)
+            if ids:
+                return ids[0]
+        return False
+
     def make_po(self, cr, uid, ids, context=None):
         res = {}
         requisition_obj = self.pool.get('purchase.requisition')