diff --git a/docker/kolla-toolbox/Dockerfile.j2 b/docker/kolla-toolbox/Dockerfile.j2
index a8c0137782..fcee30cb3b 100644
--- a/docker/kolla-toolbox/Dockerfile.j2
+++ b/docker/kolla-toolbox/Dockerfile.j2
@@ -72,10 +72,12 @@ LABEL maintainer="{{ maintainer }}" name="{{ image_name }}" build-date="{{ build
         'virtualenv'
     ] %}
 
+{% block kolla_toolbox_upper_constraints %}
 RUN mkdir -p /requirements \
     && curl -o /requirements/upper-constraints.txt https://releases.openstack.org/constraints/upper/{{ openstack_release }} \
     && {{ macros.install_pip(kolla_toolbox_pip_virtualenv_packages | customizable("pip_virtualenv_packages")) }} \
     && virtualenv --system-site-packages {{ virtualenv_path }}
+{% endblock %}
 
 ENV PATH {{ virtualenv_path }}/bin:$PATH
 
diff --git a/releasenotes/notes/add_kolla-toolbox_templating_block-3d284d886816e95a.yml b/releasenotes/notes/add_kolla-toolbox_templating_block-3d284d886816e95a.yml
new file mode 100644
index 0000000000..4fd78af68e
--- /dev/null
+++ b/releasenotes/notes/add_kolla-toolbox_templating_block-3d284d886816e95a.yml
@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Add templating block for kolla-toolbox image helping to customize
+    upper-constraints URL used at build time for offline build scenario.