The U.K. and Switzerland completed an agreement in March to settle a dispute over tax evasion by wealthy Britons holding offshore accounts with Swiss private banks. Under the agreement, customers must either make a declaration to HMRC or pay a withholding tax that also covers their past failure to disclose undeclared assets.
The U.K. is targeting residents with bank accounts held outside the country as it seeks to plug a 35 billion-pound tax gap and help reduce the nation's fiscal deficit.