Braddick said the PRA believes there is a strong case for longer deferrals.

The BoE's Prudential Regulation Authority supervises banks in Britain and its director of prudential policy Katharine Braddick said the PRA was now studying these payments.

Randell said the PRA was in contact with other agencies about the Swiss tax allegations to make sure it was dealt with "expeditiously".

Truran said the PRA could order "section 166" reviews, forcing an insurer to hire external advisors to check on the adequacy of reserving levels.