diff --git a/src/future/backports/http/cookies.py b/src/future/backports/http/cookies.py
index 8bb61e22..cdd5fd21 100644
--- a/src/future/backports/http/cookies.py
+++ b/src/future/backports/http/cookies.py
@@ -461,7 +461,8 @@ def OutputString(self, attrs=None):
     )?                             # End of optional value group
     \s*                            # Any number of spaces.
     (\s+|;|$)                      # Ending either at space, semicolon, or EOS.
-    """, re.ASCII)                 # May be removed if safe.
+    """, (re.ASCII                 # May be removed if safe.
+          | re.VERBOSE))           # Python 3.12 rejects whitespace before (?x)
 
 
 # At long last, here is the cookie class.  Using this class is almost just like