The unnamed Briton was attacked while "shopping in a store inside a gas station in Jubail province," he said, quoted by the official SPA news agency.
The victim received first aid from passers-by and was taken to hospital with a wound to his neck, but his condition is "stable" and his life is not in danger.
Security forces caught the assailant, the police chief said.

Copyright AFP (Agence France-Presse), 2006