diff --git a/addons/account/account_invoice.py b/addons/account/account_invoice.py
index 97c4685ea52..580e033e8f3 100644
--- a/addons/account/account_invoice.py
+++ b/addons/account/account_invoice.py
@@ -807,11 +807,20 @@ class account_invoice(models.Model):
 
             ctx = dict(self._context, lang=inv.partner_id.lang)
 
+            company_currency = inv.company_id.currency_id
             if not inv.date_invoice:
+                # FORWARD-PORT UP TO SAAS-6
+                if inv.currency_id != company_currency and inv.tax_line:
+                    raise except_orm(
+                        _('Warning!'),
+                        _('No invoice date!'
+                            '\nThe invoice currency is not the same than the company currency.'
+                            ' An invoice date is required to determine the exchange rate to apply. Do not forget to update the taxes!'
+                        )
+                    )
                 inv.with_context(ctx).write({'date_invoice': fields.Date.context_today(self)})
             date_invoice = inv.date_invoice
 
-            company_currency = inv.company_id.currency_id
             # create the analytical lines, one move line per invoice line
             iml = inv._get_analytic_lines()
             # check if taxes are all computed