Hello,If you have a spare key, try it as well. I strongly recommend to have the battery charger hooked up while turning the ignition.
The key and ignition must always work to turn the ignition. If it does not happen when voltage supply is ok- one of them is faulty. It is very rare that the wiring is interrupted to the ignition switch.
So if the spare key does not work as well- ignition switch will have to be replaced. Unfortunately only authorized dealers can order and replace them.