Air Conditioning Stalls Engine

I have a daewoo Espero which seems to run fine as long as the airconditioning is turned off, but with it on, the engine tends to stall whenever I am at low revs. I have experimented a bit with it and found that the problem only seems to occur when the engine is warmed up. Also when you turn it on you can feel the drop in engine performance. Any suggestions for a simple fix? At the moment the only solution seems to be to turn off the air conditioning whenever I slow down. I dont really want to go the garage and have to pay for expensive repairs.

Thanks.