diff --git a/deluge/i18n/util.py b/deluge/i18n/util.py
index f6920fbb3..f553dc8fb 100644
--- a/deluge/i18n/util.py
+++ b/deluge/i18n/util.py
@@ -66,6 +66,9 @@ def set_language(lang):
     :type lang: str
     """
     if not lang:
+        for lang_env_var in ['LANGUAGE', 'LANG']:
+            if lang_env_var in os.environ:
+                del os.environ[lang_env_var]
         return
 
     # Necessary to set these environment variables for GtkBuilder