As of the 16 March 2015 Nationwide no longer offer this service.

You can still make worldwide payments from your current account, online or in branch, using our SWIFT or SEPA services:

SEPA

For euro payments between accounts within the Single Euro Payments Area (SEPA) by SEPA Credit Transfer.

Note: SEPA Credit Transfers can only be made from current accounts.

SWIFT

For all other overseas and foreign currency payments.

Cancelling a foreign draft

If you decide not to use the draft, you should return it to your branch for cancellation. If the draft was drawn in a foreign currency, it will be converted back into sterling at the exchange rate on the day it is cancelled. The balance will be credited to your account but may be less than you originally requested as a result of exchange rate movements.
 
If the draft has been lost or stolen, you should let your branch know immediately and they will arrange for it to be stopped. You will be required to sign an indemnity covering Nationwide in the event that the original beneficiary presents the draft for payment.