diff --git a/programs/psa/CMakeLists.txt b/programs/psa/CMakeLists.txt
index 201f987..4373ceb 100644
--- a/programs/psa/CMakeLists.txt
+++ b/programs/psa/CMakeLists.txt
@@ -10,7 +10,7 @@
 
 add_custom_target(
     psa_constant_names_generated
-    COMMAND ${PYTHON_EXECUTABLE} scripts/generate_psa_constants.py ${CMAKE_CURRENT_BINARY_DIR}
+    COMMAND ${MBEDTLS_PYTHON_EXECUTABLE} scripts/generate_psa_constants.py ${CMAKE_CURRENT_BINARY_DIR}
     WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/../../
 )
 add_dependencies(psa_constant_names psa_constant_names_generated)