diff --git a/tools/psa/tfm/bin_utils/imgtool.py b/tools/psa/tfm/bin_utils/imgtool.py
index b984ce2170..0440f88fd7 100644
--- a/tools/psa/tfm/bin_utils/imgtool.py
+++ b/tools/psa/tfm/bin_utils/imgtool.py
@@ -19,9 +19,9 @@ from __future__ import print_function
 import os
 import re
 import argparse
-from imgtool_lib import keys
-from imgtool_lib import image
-from imgtool_lib import version
+from .imgtool_lib import keys
+from .imgtool_lib import image
+from .imgtool_lib import version
 import sys
 
 def find_load_address(args):