ssl_certificate = 'cat Intermediate.txt » your_domain_com.bundle'

You will need two server blocks for this:

server {
    listen 80;
    server_name www.example.co.uk example.co.uk;
    return 301 https://example.co.uk$request_uri; #note: this line actually forces https, you may not wish to have this, in which case you will just remove the line or comment it out
}
server{
    listen 443;
    server_name example.co.uk www.example.co.uk;
    root /var/www/vhosts/example.co.uk;
    index index.html index.htm index.php;

    access_log /var/log/nginx/example.co.uk.access.log;
    error_log /var/log/nginx/example.co.uk.access.log;


    ssl on;
    ssl_certificate /etc/httpd/conf/ssl/ssl.crt/example.co.uk.crt;
    ssl_certificate_key /etc/httpd/conf/ssl/ssl.key/example.co.uk.key;
    ssl_protocols TLSv1 TLSv1.1 TLSv1.2; #used to prevent poodle attacks for outdated protocols


location ~ \.php$ {
    include /etc/nginx/fastcgi_params;
    fastcgi_pass  127.0.0.1:9000;
    fastcgi_index index.php;
    fastcgi_param SCRIPT_FILENAME /var/www/vhosts/example.co.uk$fastcgi_script_name;
    }
}