diff --git a/swh/loader/mercurial/hgutil.py b/swh/loader/mercurial/hgutil.py
--- a/swh/loader/mercurial/hgutil.py
+++ b/swh/loader/mercurial/hgutil.py
@@ -1,11 +1,16 @@
+# Copyright (C) 2020-2021  The Software Heritage developers
+# See the AUTHORS file at the top-level directory of this distribution
+# License: GNU General Public License version 3, or any later version
+# See top-level LICENSE file for more information
+
 import io
-import traceback
 from multiprocessing import Process, Queue
+import traceback
 from typing import Dict, NewType
 
 # The internal Mercurial API is not guaranteed to be stable.
+from mercurial import context, hg, util  # type: ignore
 import mercurial.ui  # type: ignore
-from mercurial import context, hg, util
 
 NULLID = mercurial.node.nullid
 HgNodeId = NewType("HgNodeId", bytes)
@@ -46,7 +51,13 @@
         errors: message queue to communicate errors
     """
     try:
-        hg.clone(mercurial.ui.ui.load(), {}, src.encode(), dest.encode())
+        hg.clone(
+            ui=mercurial.ui.ui.load(),
+            peeropts={},
+            source=src.encode(),
+            dest=dest.encode(),
+            update=False,
+        )
     except Exception as e:
         exc_buffer = io.StringIO()
         traceback.print_exc(file=exc_buffer)
diff --git a/swh/loader/mercurial/loader.py b/swh/loader/mercurial/loader.py
--- a/swh/loader/mercurial/loader.py
+++ b/swh/loader/mercurial/loader.py
@@ -195,7 +195,7 @@
 
         def do_clone(queue, origin, destination):
             try:
-                result = hglib.clone(source=origin, dest=destination)
+                result = hglib.clone(source=origin, dest=destination, noupdate=True)
             except CommandError as e:
                 # the queued object need an empty constructor to be deserialized later
                 queue.put(CommandErrorWrapper(e.err))
diff --git a/swh/loader/mercurial/tests/test_hgutil.py b/swh/loader/mercurial/tests/test_hgutil.py
--- a/swh/loader/mercurial/tests/test_hgutil.py
+++ b/swh/loader/mercurial/tests/test_hgutil.py
@@ -1,4 +1,4 @@
-# Copyright (C) 2020  The Software Heritage developers
+# Copyright (C) 2020-2021  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
@@ -6,8 +6,8 @@
 import time
 import traceback
 
-import pytest
 from mercurial import hg  # type: ignore
+import pytest
 
 from .. import hgutil
 
@@ -17,7 +17,7 @@
     dest = "/dev/null"
     timeout = 1
 
-    def clone(*args):
+    def clone(*args, **kwargs):
         time.sleep(5)
 
     monkeypatch.setattr(hg, "clone", clone)
@@ -32,7 +32,7 @@
     dest = "/dev/null"
     expected_traceback = "Some traceback"
 
-    def clone(*args):
+    def clone(*args, **kwargs):
         raise ValueError()
 
     def print_exc(file):
diff --git a/swh/loader/mercurial/tests/test_loader.py b/swh/loader/mercurial/tests/test_loader.py
--- a/swh/loader/mercurial/tests/test_loader.py
+++ b/swh/loader/mercurial/tests/test_loader.py
@@ -57,11 +57,7 @@
     )
 
     assert_last_visit_matches(
-        swh_storage,
-        repo_url,
-        status="full",
-        type="hg",
-        snapshot=expected_snapshot.id,
+        swh_storage, repo_url, status="full", type="hg", snapshot=expected_snapshot.id,
     )
     check_snapshot(expected_snapshot, swh_storage)
 
@@ -325,7 +321,7 @@
 def test_clone_with_timeout_timeout(caplog, tmp_path, monkeypatch):
     log = logging.getLogger("test_clone_with_timeout")
 
-    def clone_timeout(source, dest):
+    def clone_timeout(source, dest, *args, **kwargs):
         time.sleep(60)
 
     monkeypatch.setattr(hglib, "clone", clone_timeout)
@@ -344,7 +340,7 @@
 def test_clone_with_timeout_returns(caplog, tmp_path, monkeypatch):
     log = logging.getLogger("test_clone_with_timeout")
 
-    def clone_return(source, dest):
+    def clone_return(source, dest, *args, **kwargs):
         return (source, dest)
 
     monkeypatch.setattr(hglib, "clone", clone_return)
@@ -357,7 +353,7 @@
 def test_clone_with_timeout_exception(caplog, tmp_path, monkeypatch):
     log = logging.getLogger("test_clone_with_timeout")
 
-    def clone_return(source, dest):
+    def clone_return(source, dest, *args, **kwargs):
         raise ValueError("Test exception")
 
     monkeypatch.setattr(hglib, "clone", clone_return)