diff --git a/Modules/ExternalProject.cmake b/Modules/ExternalProject.cmake
index 0df51a878..17cb866d3 100644
--- a/Modules/ExternalProject.cmake
+++ b/Modules/ExternalProject.cmake
@@ -605,7 +605,7 @@ does not match expected value
 Retrying download.
 \")
     file(REMOVE \"\${file}\")
-    execute_process(COMMAND ${CMAKE_COMMAND} -P \"${download_script}\")
+    execute_process(COMMAND \${CMAKE_COMMAND} -P \"${download_script}\")
   endif()
 endwhile()