diff --git a/google/colab/output/__init__.py b/google/colab/output/__init__.py
index 3c73fc5c..dd57e9d5 100644
--- a/google/colab/output/__init__.py
+++ b/google/colab/output/__init__.py
@@ -14,7 +14,7 @@
 """Colabs output package."""
 # pylint: disable=g-multiple-import
 from google.colab.output._area import redirect_to_element, to_default_area, to_footer_area, to_header_area
-from google.colab.output._js import eval_js, register_callback
+from google.colab.output._js import eval_js, register_callback, unregister_callback
 from google.colab.output._tags import clear, temporary, use_tags
 from google.colab.output._util import serve_kernel_port_as_iframe, serve_kernel_port_as_window
-from google.colab.output._widgets import enable_custom_widget_manager, disable_custom_widget_manager
+from google.colab.output._widgets import disable_custom_widget_manager, enable_custom_widget_manager
diff --git a/google/colab/output/_js.py b/google/colab/output/_js.py
index 52909ffd..9c0e2387 100644
--- a/google/colab/output/_js.py
+++ b/google/colab/output/_js.py
@@ -61,6 +61,23 @@ def register_callback(function_name, callback):
   _functions[function_name] = callback
 
 
+def unregister_callback(function_name):
+  """Removes a function previously registered by register_callback.
+
+  Args:
+    function_name: string
+
+  Raises:
+    ValueError: if a callback is not currently registered to function_name.
+  """
+  try:
+    del _functions[function_name]
+  except KeyError as e:
+    raise ValueError(
+        f'Callback function not registered: {function_name}.'
+    ) from e
+
+
 def _invoke_function(function_name, json_args, json_kwargs):
   """Invokes callback with given function_name.