diff --git a/changelog.d/3434.deprecation.rst b/changelog.d/3434.deprecation.rst
new file mode 100644
index 00000000000..2073d2b91a8
--- /dev/null
+++ b/changelog.d/3434.deprecation.rst
@@ -0,0 +1,3 @@
+Added deprecation warning for ``pkg_resources.declare_namespace``.
+Users that wish to implement namespace packages, are recommended to follow the
+practice described in PEP 420 and omit the ``__init__.py`` file entirely.