Huawei G700 keeps asking permission to use mobile data after WiFi disconnects
It seems that this behavior is present in all recent Chinese ROMs from Huawei and there is no way to disable it. However, I found a workaround for it; The message only popsup if you have WiFi and Data Enabled and you lose WiFi connectivity. Then your phone will ask if it's allowed to switch from WiFi to Data. So, if you make sure WiFi is disabled before switching to Data, it will not ask this question. To do so manually, takes a lot of time. Luckily there is an app that can automate this task for you. Here's how:

Install the app 'Llama' from the Market (Free) and create these two events:



The 1 second delay is necessary, else it does not work properly.

What it does: Switch off WiFi as soon WiFi disconnects from your WiFi network and then enables Data. This way, it does not show the popup and 'automatically' switch to Data. Don't forget to manually enable WiFi again if you are in reach again of your WiFi network.
If you want Llama to automatically turn back WiFi on as soon you get home/in reach of your WiFi, you have to let it learn your location. Read the help/documentention on how to do so. It's pretty easy to do :)

This 'fix' works for me 9 out 10 times. Give it a try, I hope it helps you.