thre should be no problems washing prints if they are dirty or have marks you wish to remove - the final stage in the printing process before the print is dried is washing.
Ilford make a product similar to what Mark has mentioned - I think called "Ilfotol"? - it's referred to as a wetting agent - and stops drying marks on the surface of the print as water evaporates from it. Alternatively, you could use a VERY WEAK solution of fairy liquid, which has a similar effect (not quite as good), but you probably have to hand. Paterson make a print squeege to remove excess water and aid drying - but you could lay the print flat and use a window cleaner's squeege (but make sure it's CLEAN - you don't want scratches). Squeege-ing the print before leaving to dry will drastically reduce the drying time, and also reduce any drying marks you might get.
A word of caution - some marks and debris on the surface of a print could actually damage the emulsion. In this case, it might not be obvious before you start, but washing the print would remove the marks AND the emulsion that's underneath them! I would say this is the exception rather than the rule - prints are pretty resilient if they have been properly processed in the first place, but I thought it worth a warning note.