diff --git a/lisp/gnus/nnimap.el b/lisp/gnus/nnimap.el
index 570be49094..f869f586d9 100644
--- a/lisp/gnus/nnimap.el
+++ b/lisp/gnus/nnimap.el
@@ -1076,7 +1076,9 @@ nnimap-process-expiry-targets
                   "UID COPY %s %S")
                 (nnimap-article-ranges (gnus-compress-sequence articles))
                 (nnimap-group-to-imap (gnus-group-real-name nnmail-expiry-target)))
-               (set (if can-move 'deleted-articles 'articles-to-delete) articles))))
+               (if can-move
+                   (setq deleted-articles articles)
+                 (setq articles-to-delete articles)))))
       t)
      (t
       (dolist (article articles)