diff --git a/include/psa/crypto_config.h b/include/psa/crypto_config.h
index af78dce177..d8e8e19d0a 100644
--- a/include/psa/crypto_config.h
+++ b/include/psa/crypto_config.h
@@ -92,7 +92,8 @@
 #define PSA_WANT_ALG_TLS12_PSK_TO_MS            1
 #define PSA_WANT_ALG_TLS12_ECJPAKE_TO_PMS       1
 
-/* Note: when adding support, also adjust include/mbedtls/config_psa.h */
+/* XTS is not yet supported via the PSA API in Mbed TLS.
+ * Note: when adding support, also adjust include/mbedtls/config_psa.h */
 //#define PSA_WANT_ALG_XTS                        1
 
 #define PSA_WANT_ECC_BRAINPOOL_P_R1_256         1