diff --git a/pywikibot/site/_apisite.py b/pywikibot/site/_apisite.py
index 81c3a85e5a..3802d23b29 100644
--- a/pywikibot/site/_apisite.py
+++ b/pywikibot/site/_apisite.py
@@ -1246,6 +1246,14 @@ def version(self) -> str:
             pywikibot.error(msg)
             raise
 
+        if MediaWikiVersion(version) < '1.31':
+            warn('\n'
+                 + fill(f'Support of MediaWiki {version} will be dropped. '
+                        'It is recommended to use MediaWiki 1.31 or above. '
+                        'You may use every Pywikibot 9.X for older MediaWiki '
+                        'versions. See T378984 for further information.'),
+                 FutureWarning)
+
         if MediaWikiVersion(version) < '1.27':
             raise RuntimeError(f'Pywikibot "{pywikibot.__version__}" does not '
                                f'support MediaWiki "{version}".\n'