diff --git a/swh/deposit/tests/api/test_deposit_atom.py b/swh/deposit/tests/api/test_deposit_atom.py
--- a/swh/deposit/tests/api/test_deposit_atom.py
+++ b/swh/deposit/tests/api/test_deposit_atom.py
@@ -50,14 +50,16 @@
     """Posting empty body request should return a 400 response
 
     """
-    response = authenticated_client.post(
-        reverse(COL_IRI, args=[deposit_collection.name]),
-        content_type="application/atom+xml;type=entry",
-        data=atom_dataset["entry-data-empty-body"],
-        HTTP_SLUG="external-id",
-    )
-    assert response.status_code == status.HTTP_400_BAD_REQUEST
-    assert b"Empty body request is not supported" in response.content
+    for atom_key in ["entry-data-empty-body", "entry-data-empty-body-no-namespace"]:
+        atom_content = atom_dataset[atom_key]
+        response = authenticated_client.post(
+            reverse(COL_IRI, args=[deposit_collection.name]),
+            content_type="application/atom+xml;type=entry",
+            data=atom_content,
+            HTTP_SLUG="external-id",
+        )
+        assert response.status_code == status.HTTP_400_BAD_REQUEST
+        assert b"Empty body request is not supported" in response.content
 
 
 def test_post_deposit_atom_400_badly_formatted_atom(
diff --git a/swh/deposit/tests/api/test_deposit_update.py b/swh/deposit/tests/api/test_deposit_update.py
--- a/swh/deposit/tests/api/test_deposit_update.py
+++ b/swh/deposit/tests/api/test_deposit_update.py
@@ -763,15 +763,17 @@
         EDIT_SE_IRI, args=[deposit_collection.name, complete_deposit.id]
     )
 
-    response = authenticated_client.put(
-        update_uri,
-        content_type="application/atom+xml;type=entry",
-        data=atom_dataset["entry-data-empty-body"],
-        HTTP_X_CHECK_SWHID=complete_deposit.swh_id,
-    )
-
-    assert response.status_code == status.HTTP_400_BAD_REQUEST
-    assert b"Empty body request is not supported" in response.content
+    for atom_key in ["entry-data-empty-body", "entry-data-empty-body-no-namespace"]:
+        atom_content = atom_dataset[atom_key]
+        response = authenticated_client.put(
+            update_uri,
+            content_type="application/atom+xml;type=entry",
+            data=atom_content,
+            HTTP_X_CHECK_SWHID=complete_deposit.swh_id,
+        )
+
+        assert response.status_code == status.HTTP_400_BAD_REQUEST
+        assert b"Empty body request is not supported" in response.content
 
 
 def test_put_update_metadata_done_deposit_failure_functional_checks(
diff --git a/swh/deposit/tests/data/atom/entry-data-empty-body.xml b/swh/deposit/tests/data/atom/entry-data-empty-body-no-namespace.xml
copy from swh/deposit/tests/data/atom/entry-data-empty-body.xml
copy to swh/deposit/tests/data/atom/entry-data-empty-body-no-namespace.xml
diff --git a/swh/deposit/tests/data/atom/entry-data-empty-body.xml b/swh/deposit/tests/data/atom/entry-data-empty-body.xml
--- a/swh/deposit/tests/data/atom/entry-data-empty-body.xml
+++ b/swh/deposit/tests/data/atom/entry-data-empty-body.xml
@@ -1,2 +1,2 @@
 <?xml version="1.0"?>
-<entry></entry>
+<entry xmlns="http://www.w3.org/2005/Atom"></entry>