diff --git a/boot/zephyr/Kconfig b/boot/zephyr/Kconfig
index 988c329c86..d2c64322d2 100644
--- a/boot/zephyr/Kconfig
+++ b/boot/zephyr/Kconfig
@@ -213,7 +213,7 @@ config BOOT_SIGNATURE_TYPE_RSA
 	select BOOT_USE_MBEDTLS
 	select MBEDTLS
 	select MBEDTLS_ASN1_PARSE_C if MBEDTLS_BUILTIN
-	select MBEDTLS_KEY_EXCHANGE_RSA_ENABLED if MBEDTLS_BUILTIN
+	select MBEDTLS_RSA_C if MBEDTLS_BUILTIN
 	select BOOT_ENCRYPTION_SUPPORT
 	select BOOT_IMG_HASH_ALG_SHA256_ALLOW
 	select BOOT_AES_MBEDTLS_DEPENDENCIES if MBEDTLS_BUILTIN && BOOT_ENCRYPT_IMAGE