Their website now displays the following message :
THE BRITISH EMBASSY IS NOW CLOSED
The British Embassy is now CLOSED until further notice for all normal business, including VISA applications.
We are now dealing exclusively with the 26 December Tsunami disaster, and are open on an emergency 24 hour basis for those requiring assistance as a result. For Disaster enquiries please telephone: 02 305 8333 or e-mail: Consular.Bangkok@fco.gov.uk