A Saudi Man can marry a non-saudi woman only after the permission of the govt. These days they are very strict and they don't give permission easily. They can marry outside of Saudia without the permission but the man will be fined 100,000 Riyals and the wife will NOT be RECOGNIZED as a legal wife here in Saudia and might face legal problems like VISA. It is better that the nikah takes place after the permission letter has been attained from the Saudi Govt.