diff --git a/disk_objectstore/container.py b/disk_objectstore/container.py
index 05f5481..0f4393c 100644
--- a/disk_objectstore/container.py
+++ b/disk_objectstore/container.py
@@ -1340,6 +1340,15 @@ def pack_all_loose(  # pylint: disable=too-many-locals,too-many-branches,too-man
             Needed to guarantee that data will be there even in the case of a power loss.
             Set to False if you don't need such a guarantee (anyway the loose version will be kept,
             so often this guarantee is not strictly needed).
+        :param callback: a callback function that can be used to report progress.
+            The callback function should accept two arguments: a string with the action being performed
+            and the value of the action. The action can be "init" (initialization),
+            "update" (update of the progress), or "close" (finalization).
+            In case of "init", the value is a dictionary with the key "total" as the total size of the operation
+            and key "description" as the label of the operation.
+            In case of "update", the value is amount of the operation that has been completed.
+            In case of "close", the value is None.
+            return value of the callback function is ignored.
         """
         hash_type = self.hash_type if validate_objects else None
 
@@ -2611,6 +2620,15 @@ def repack(
         This is a maintenance operation.
 
         :param compress_mode: see docstring of ``repack_pack``.
+        :param callback: a callback function that can be used to report progress.
+            The callback function should accept two arguments: a string with the action being performed
+            and the value of the action. The action can be "init" (initialization),
+            "update" (update of the progress), or "close" (finalization).
+            In case of "init", the value is a dictionary with the key "total" as the total size of the operation
+            and key "description" as the label of the operation.
+            In case of "update", the value is amount of the operation that has been completed.
+            In case of "close", the value is None.
+            return value of the callback function is ignored.
         """
         for pack_id in self._list_packs():
             self.repack_pack(pack_id, compress_mode=compress_mode, callback=callback)
@@ -2631,6 +2649,15 @@ def repack_pack(  # pylint: disable=too-many-branches,too-many-statements,too-ma
             preserves the same compression (this means that repacking is *much* faster
             as it can simply transfer the bytes without decompressing everything first,
             and recompressing it back again).
+        :param callback: a callback function that can be used to report progress.
+            The callback function should accept two arguments: a string with the action being performed
+            and the value of the action. The action can be "init" (initialization),
+            "update" (update of the progress), or "close" (finalization).
+            In case of "init", the value is a dictionary with the key "total" as the total size of the operation
+            and key "description" as the label of the operation.
+            In case of "update", the value is amount of the operation that has been completed.
+            In case of "close", the value is None.
+            return value of the callback function is ignored.
         """
         assert (
             pack_id != self._REPACK_PACK_ID
diff --git a/tests/test_container.py b/tests/test_container.py
index dae8841..f0c89e5 100644
--- a/tests/test_container.py
+++ b/tests/test_container.py
@@ -3446,6 +3446,36 @@ def test_repack_auto_many_sizes(temp_container: Container, start_compressed):
     assert issues.is_valid()
 
 
+def test_repack_progress_bar(temp_container: Container):
+    """Check that the progress bar is correctly updated when packing all loose objects."""
+    objects = []
+    for length in range(0, 100):
+        objects.append(b"a" * length)
+
+    temp_container.add_objects_to_pack(objects, compress=False)
+
+    passed_updates = 0
+    passed_total = 0
+
+    def progress(action, value):
+        """A dummy progress function."""
+        if action == "init":
+            assert (
+                value["total"] == temp_container.get_total_size()["total_size_packed"]
+            )
+            nonlocal passed_total
+            passed_total = value["total"]
+            assert value["description"] == "Repack 0"
+        elif action == "update":
+            isinstance(value, (int, float))
+            nonlocal passed_updates
+            passed_updates += value
+        elif action == "close":
+            assert passed_updates == passed_total
+
+    temp_container.repack(callback=progress)
+
+
 @pytest.mark.parametrize("compress_mode", [True, False] + list(CompressMode))
 def test_pack_all_loose_compress_modes(temp_container: Container, compress_mode):
     """Check that pack_all_loose() uses the correct compression mode.
@@ -3518,6 +3548,33 @@ def test_pack_all_loose_many(temp_container):
     assert retrieved == expected
 
 
+def test_pack_all_loose_progress_bar(temp_container):
+    """Check that the progress bar is correctly updated when packing all loose objects."""
+    # Add 10 objects
+    for idx in range(10):
+        content = f"{idx}".encode()
+        temp_container.add_object(content)
+
+    passed_updates = 0
+    passed_total = 0
+
+    def progress(action, value):
+        """A dummy progress function."""
+        if action == "init":
+            assert value["total"] == temp_container.get_total_size()["total_size_loose"]
+            nonlocal passed_total
+            passed_total = value["total"]
+            assert value["description"] == "Packing loose objects"
+        elif action == "update":
+            isinstance(value, (int, float))
+            nonlocal passed_updates
+            passed_updates += value
+        elif action == "close":
+            assert passed_updates == passed_total
+
+    temp_container.pack_all_loose(callback=progress)
+
+
 def test_container_id(temp_container):
     """Check the creation of unique container IDs."""
     old_container_id = temp_container.container_id