query_vars and htaccess

hi, i’ve a (hope) little problem with wordpress.

I’ve a page like

http://www.site.com/football

i want pass two var to this url, so i’ve setting up this code in my functions.php

function add_query_vars_filter( $vars ){
  $vars[] = "id_country";
  $vars[] = "id_league";
  return $vars;
}
add_filter( 'query_vars', 'add_query_vars_filter' );

I like to have urls, only for this page, like this

http://www.site.com/football/england/premier.html

that is

http://www.site.com/football?id_country=england&id_league=premier

so, how can i edit my actual htaccess?

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d

RewriteRule . /index.php [L]

</IfModule>

# END WordPress

Thanks in advance!