diff --git a/interfaces/cython/cantera/__init__.py b/interfaces/cython/cantera/__init__.py
index 2703eb17e..d1dfcb99a 100644
--- a/interfaces/cython/cantera/__init__.py
+++ b/interfaces/cython/cantera/__init__.py
@@ -4,4 +4,9 @@ from .liquidvapor import *
 from .utils import *
 
 import os as _os
+import sys as _sys
 add_directory(_os.path.join(_os.path.dirname(__file__), 'data'))
+
+# Python interpreter used for converting mechanisms
+if 'PYTHON_CMD' not in _os.environ:
+    _os.environ['PYTHON_CMD'] = _sys.executable