diff --git a/bin/tools/yaml_import.py b/bin/tools/yaml_import.py
index 87fd2ff432c..b307eb93ef1 100644
--- a/bin/tools/yaml_import.py
+++ b/bin/tools/yaml_import.py
@@ -374,6 +374,14 @@ class YamlInterpreter(object):
         elif column._type == "many2many":
             ids = [self.get_id(xml_id) for xml_id in expression]
             value = [(6, 0, ids)]
+        elif column._type == "date":
+            # enforce ISO format for date values, to be locale-agnostic during tests
+            time.strptime(expression, "%Y-%m-%d")
+            value = expression
+        elif column._type == "datetime":
+            # enforce ISO format for date values, to be locale-agnostic during tests
+            time.strptime(expression, "%Y-%m-%d %H:%M:%S")
+            value = expression
         else: # scalar field
             if is_eval(expression):
                 value = self.process_eval(expression)