diff --git a/library/ssl_client.c b/library/ssl_client.c
index a975d6a..7acb725 100644
--- a/library/ssl_client.c
+++ b/library/ssl_client.c
@@ -963,7 +963,9 @@
                                                               buf_len,
                                                               msg_len));
 
+#if defined(MBEDTLS_SSL_PROTO_TLS1_3)
         mbedtls_ssl_tls13_finalize_write_client_hello(ssl);
+#endif
 
     }
 
diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index e2efabd..29a60ec 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -2740,6 +2740,8 @@
 }
 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_SESSION_TICKETS */
 
+#if defined(MBEDTLS_SSL_CLI_C) && defined(MBEDTLS_SSL_PROTO_TLS1_3)
 int mbedtls_ssl_tls13_finalize_write_client_hello(mbedtls_ssl_context *ssl);
+#endif
 
 #endif /* ssl_misc.h */