The contact details for the British Embassy in Liechtenstein is listed below. Please note that this embassy is located in Berne in Switzerland very close to the Thai embassy in Switzerland. Call or email them before you arrive at the embassy. They do note that you have to make an appointment for certain services which they do offer. The contact details are below with a map to the embassy.
British Embassy in Liechtenstein
Office hours: Monday to Friday, 8am to 12.30pm and 1.30pm to 5pm
Consular hours: Monday to Friday, 8.30am to 12.30pm
Notarial services: Notarial services are by appointment only.