use XML::Twig;

  my $twig=XML::Twig->new(   
    twig_handlers => 
      {
        link => sub {  if($counter == 0){$_->delete; $counter++;}  },  #
      },
    pretty_print => 'indented', 
                         );
    $twig->parsefile( 'doc.xml');
    $twig->flush;