Welcome to Mac-Forums. The correct subforum (for future reference) would be Powerbook/MacBook Pro. This subforum is for Comments, Suggestions and questions about the board itself.
You would need the international power adapter kit as the standard US power supply only has connectors for 110 outlets. In addition, you will not have a UK keyboard, so it will have a $ key instead of a £ key. There may also be warranty issues should you ever need service.