diff --git a/requirements.txt b/requirements.txt
index e1a5faf6a3f..fc6a5efce4b 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,7 +2,7 @@ sphinx-intl==2.1.0
 powrap==1.0.1
 
 # Dependencies for scripts/lock-translations.py
-python-dateutil==2.8.2
+python-dateutil==2.9.0.post0
 transifex-python==3.5.0
 
 # Dependencies required by scripts/manage_versions.py