diff --git a/soc/silabs/silabs_siwx917/CMakeLists.txt b/soc/silabs/silabs_siwx917/CMakeLists.txt
index 3f9963b..1a18dc0 100644
--- a/soc/silabs/silabs_siwx917/CMakeLists.txt
+++ b/soc/silabs/silabs_siwx917/CMakeLists.txt
@@ -6,7 +6,6 @@ add_subdirectory(siwg917)
 set_property(GLOBAL APPEND PROPERTY extra_post_build_commands
     COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/siwx917_isp_prepare.py
     --rom_addr ${CONFIG_FLASH_BASE_ADDRESS}
-    --out_hex ${KERNEL_HEX_NAME}
     ${KERNEL_BIN_NAME}
     ${KERNEL_BIN_NAME}.rps
 )