diff --git a/scripts/imgtool/keys/ecdsa.py b/scripts/imgtool/keys/ecdsa.py
index b70153c88e..70701258ed 100644
--- a/scripts/imgtool/keys/ecdsa.py
+++ b/scripts/imgtool/keys/ecdsa.py
@@ -179,7 +179,7 @@ def verify(self, signature, payload):
                         signature_algorithm=ec.ECDSA(SHA256()))
 
 
-class ECDSA256P1(ECDSA256P1Public, ECDSAPrivateKey):
+class ECDSA256P1(ECDSAPrivateKey, ECDSA256P1Public):
     """
     Wrapper around an ECDSA (p256) private key.
     """
@@ -252,7 +252,7 @@ def verify(self, signature, payload):
                         signature_algorithm=ec.ECDSA(SHA384()))
 
 
-class ECDSA384P1(ECDSA384P1Public, ECDSAPrivateKey):
+class ECDSA384P1(ECDSAPrivateKey, ECDSA384P1Public):
     """
     Wrapper around an ECDSA (p384) private key.
     """