[R] regex sulotion for seperating number and string

[sun]

I have strings contain postcode and letters, some seperated with blank, some 
with comma, and some hasn't seperated. eg, "2324gz"  "2567 HK" "3741,BF"

I want to seperate the number and letters into two new variables.

I know this should be quite basic question, but searched on regex syntax and 
that seems a bit scarey to me, any one can shot me a quick solution on this 
particular question?

thanks,
Sun