diff --git a/build-scripts/compose_ds.py b/build-scripts/compose_ds.py
index b5808a61b66c..decdc19364f5 100755
--- a/build-scripts/compose_ds.py
+++ b/build-scripts/compose_ds.py
@@ -282,10 +282,10 @@ def upgrade_ds_to_scap_13(ds):
 
 def _store_ds(ds, output_13, output_12):
     if output_12:
-        ds.write(output_12)
+        ds.write(output_12, xml_declaration=True)
 
     ds_13 = upgrade_ds_to_scap_13(ds)
-    ds_13.write(output_13)
+    ds_13.write(output_13, xml_declaration=True)
 
 
 def append_id_to_file_name(path, id_):
diff --git a/ssg/build_yaml.py b/ssg/build_yaml.py
index 6471a4d4a251..a8aa55858951 100644
--- a/ssg/build_yaml.py
+++ b/ssg/build_yaml.py
@@ -1587,7 +1587,7 @@ def export_ocil_to_file(self, filename):
         if root is None:
             return
         tree = ET.ElementTree(root)
-        tree.write(filename)
+        tree.write(filename, xml_declaration=True)
 
 
 class Platform(XCCDFEntity):