diff --git a/backup/converter/moodle1/handlerlib.php b/backup/converter/moodle1/handlerlib.php
index a6b77886b99..f0c97541ca9 100644
--- a/backup/converter/moodle1/handlerlib.php
+++ b/backup/converter/moodle1/handlerlib.php
@@ -345,6 +345,8 @@ class moodle1_root_handler extends moodle1_xml_handler {
         // {@see backup_general_helper::backup_is_samesite()}
         if (isset($backupinfo['original_site_identifier_hash'])) {
             $this->xmlwriter->full_tag('original_site_identifier_hash', $backupinfo['original_site_identifier_hash']);
+        } else {
+            $this->xmlwriter->full_tag('original_site_identifier_hash', null);
         }
         $this->xmlwriter->full_tag('original_course_id', $originalcourseinfo['original_course_id']);
         $this->xmlwriter->full_tag('original_course_fullname', $originalcourseinfo['original_course_fullname']);