diff --git a/fastkml/geometry.py b/fastkml/geometry.py
index baff7f39..45021891 100644
--- a/fastkml/geometry.py
+++ b/fastkml/geometry.py
@@ -605,10 +605,10 @@ def etree_element(
     ) -> Element:
         self.__name__ = self.__class__.__name__
         element = super().etree_element(precision=precision, verbosity=verbosity)
-        assert isinstance(self.geometry, geo._MultiGeometry)
         _map_to_kml = {mg: self.__class__ for mg in self.multi_geometries}
         _map_to_kml.update(self.map_to_kml)
-
+        if self.geometry is None:
+            return element
         for geometry in self.geometry.geoms:
             geometry_class = _map_to_kml[type(geometry)]
             element.append(
diff --git a/tests/geometries/multigeometry_test.py b/tests/geometries/multigeometry_test.py
index 02046bef..00c26437 100644
--- a/tests/geometries/multigeometry_test.py
+++ b/tests/geometries/multigeometry_test.py
@@ -345,6 +345,18 @@ def test_multi_geometries_read(self) -> None:
             )
         )
 
+    def test_empty_multi_geometries_read(self) -> None:
+        xml = (
+            "<MultiGeometry><extrude>0</extrude><tessellate>0</tessellate>"
+            "<MultiGeometry></MultiGeometry></MultiGeometry>"
+        )
+
+        mg = MultiGeometry.class_from_string(xml, ns="")
+
+        assert mg.geometry is None
+        assert "MultiGeometry>" in mg.to_string()
+        assert "coordinates>" not in mg.to_string()
+
 
 class TestMultiPointLxml(Lxml, TestMultiPointStdLibrary):
     """Test with lxml."""