Requirements: Business Visa (single entry or 3/6 month multiple entry)
Either:
A letter of invitation from the Saudi sponsor company endorsed by the Saudi Chamber of Commerce
or
Visa Authority from the Ministry of Foreign Affairs
Letter of support addressed to the Saudi Embassy from UK/ European employing company (not required if you have Visa Authority from Ministry of Foreign Affairs)
Two passport photos
Passport (valid at least 6 months and with 2 facing blank pages)