You dont have to be american, you can be from the UK but here are the requirements-
You are a permanent UK resident either creating a project in your own name or on behalf of a legal entity with a Companies House Number.
You have a UK address, UK bank account, and government-issued ID (driver's license or passport).
You have a major UK credit or debit card.
You are 18 years of age or older.
Kickstarter to the UK has been on for a while now...