Stone chips, light rust?

[Mac456]

Hi,
After washing my car yesterday I noticed two stone chips on the roof which have a little surface rust.
What is the best way to touch these up?

I have read about lightly sanding them but the stone chips are no bigger then 2mm so I don't see how this is possible without ruining the surrounding paint.

If I leave them (only I will spot them) is it likely to get worse? My old VW had quite a lot of stone chips on the bonnet which never seemed to get worse (spread) for the years I had it.

I have only had the car for a few months (used, bought from the main dealer) and I am guessing they will not help me with this.

Thanks.

 

[artyman]

The thing to do is remove the rust that is present, use a sharp pointed implement, then prime and paint the clean metal. Probably quite deep so build up in layers over a few days