Stop Checkout without Shipping

[3D Wall]

Hi

 

Ive noticed on my cart (Presta 1.6) that the users can actually proceed without choosing a shipping method. I have it set so the cart doesn't show shipping price until they choose a shipping option as there are 3 options, standard, economy and overseas, but they can still go to "Proceed to Checkout" and continue without choosing shipping. Is there a way of making it so if they choose "Proceed to Checkout" without choosing a shipping option, that it then tells them they cant proceed until they do?

 

Many Thanks

Paul

Edited August 21, 2014 by 3D Wall (see edit history)