How to close access to the site for RIPE NCC?

Question

Fight against spam

Greetings!
Please tell me how to close access to the site for RIPE NCC?

Answer 1

<?php
if($SERVER["HTTP_USER_AGENT"] == "RIPE NCC"){
die("Доступ запрещен!");
}
?>

Answer 2

RIPE NCC is responsible for all addresses in Europe, Russia and the Middle East. Do you really need it?