What is the wattage of the lights??
For the purpose of this post, I'll assume that they are 55w each. So first... some math.
55w + 55w = 110w
110w / 12v = 9.167A
The math above shows that the lights will be consuming roughly 9 amps when they are on. I would not recommend directly attaching to your fog light circuit as the wire gauge and fuse will not support the additional drain. However, you can use the fog light circuit to trigger a relay in order for the new lights to operate at the same time.
If you are famaliar with a standard automotive relay, you will know that the 5 pins are labled 30, 85, 86, 87, 87a. I'm not at the computer that has software to draw schematics but this is the text version:
85 - switched ground from interior mounted switch
86 - connect to factory fog light wire that shows +12v when on
30 - +12v output to both new lights
87 - 10 apm FUSED input from battery
87a - No connection
Both lights would have to be chassis grounded.
The interior switch can be any ON/OFF switch such as a rocker, illuminated rocker, push-in, ect. there are no special requirements for the switch as it will be a low current application.