Engine die off once i start the A/C

[Dieudonne]

Just what might i look for when my (2004 Vovlo S 60, clock 162000Km) that once i start the A/C the car runs for about a Kilometer and then engine dies off, but with all other light on and music playing. I then have to restart the car to continue. its dangerous to have your car suddenly unable to move in the middle of road with other cars probably speeding you. just what could the problem?