diff --git a/core/modules/book/book.module b/core/modules/book/book.module
index d6fd482..e113661 100644
--- a/core/modules/book/book.module
+++ b/core/modules/book/book.module
@@ -447,7 +447,7 @@ function _book_add_form_elements(&$form, &$form_state, EntityInterface $node) {
     '#description' => t('Pages at a given level are ordered first by weight and then by title.'),
   );
   $options = array();
-  $nid = $node->id() ? $node->id() : 'new';
+  $nid = !$node->isNew() ? $node->id() : 'new';
 
   if ($node->id() && ($nid == $node->book['original_bid']) && ($node->book['parent_depth_limit'] == 0)) {
     // This is the top level node in a maximum depth book and thus cannot be moved.