diff --git a/addons/project_purchase/models/project_project.py b/addons/project_purchase/models/project_project.py
index 0eb3004b80c..c2b6d490628 100644
--- a/addons/project_purchase/models/project_project.py
+++ b/addons/project_purchase/models/project_project.py
@@ -134,7 +134,7 @@ class Project(models.Model):
             self._cr.execute(query_string, query_param)
             purchase_order_line_read = [{
                 **pol,
-                'invoice_lines': self.env['purchase.order.line'].browse(pol['id']).invoice_lines,  # One2Many cannot be queried, they are not columns
+                'invoice_lines': self.env['purchase.order.line'].browse(pol['id']).sudo().invoice_lines,  # One2Many cannot be queried, they are not columns
             } for pol in self._cr.dictfetchall()]
             purchase_order_line_invoice_line_ids = self._get_already_included_profitability_invoice_line_ids()
             with_action = with_action and self.user_has_groups('purchase.group_purchase_user, account.group_account_invoice, account.group_account_readonly')