diff --git a/addons/purchase_requisition/models/purchase_requisition.py b/addons/purchase_requisition/models/purchase_requisition.py
index d9d7b4e2055..fd4a19e8b39 100644
--- a/addons/purchase_requisition/models/purchase_requisition.py
+++ b/addons/purchase_requisition/models/purchase_requisition.py
@@ -291,6 +291,7 @@ class PurchaseOrder(models.Model):
     _inherit = "purchase.order"
 
     requisition_id = fields.Many2one('purchase.requisition', string='Purchase Agreement', copy=False)
+    is_quantity_copy = fields.Selection(related='requisition_id.is_quantity_copy')
 
     @api.onchange('requisition_id')
     def _onchange_requisition_id(self):
diff --git a/addons/purchase_requisition/views/purchase_requisition_views.xml b/addons/purchase_requisition/views/purchase_requisition_views.xml
index 01d90b20a6f..93030beeb2c 100644
--- a/addons/purchase_requisition/views/purchase_requisition_views.xml
+++ b/addons/purchase_requisition/views/purchase_requisition_views.xml
@@ -79,9 +79,8 @@
         <field name="inherit_id" ref="purchase.purchase_order_form"/>
         <field name="arch" type="xml">
           <field name="partner_id" position="replace">
-            <field name="partner_id" context="{'search_default_supplier':1, 'default_supplier':1, 'default_customer':0}"
-              domain="[('supplier','=',True)]"
-              attrs="{'readonly': ['&amp;', ('partner_id', '!=', False), ('requisition_id','!=', False)]}" force_save="1"/>
+            <field name="is_quantity_copy" invisible="1"/>
+            <field name="partner_id" context="{'search_default_supplier':1, 'default_supplier':1, 'default_customer':0}" domain="[('supplier','=',True)]" attrs="{'readonly': ['|', ('is_quantity_copy', '=', 'none'), ('state', 'in', ['purchase', 'done', 'cancel'])]}" force_save="1"/>
             </field>
             <field name="partner_ref" position="after">
                 <field name="requisition_id"