Six top UK law firms have joined forces to urge the Securities and Exchange Commission (SEC) to grant foreign lawyers temporary exemption from its tough new regulatory powers, claiming they could face criminal sanctions if they comply with its rules.

In a joint submission to the SEC, the firms – Allen & Overy, Freshfields Bruckhaus Deringer, Herbert Smith, Linklaters, Lovells and Norton Rose – warn that controversial provisions requiring lawyers to whistleblow on their clients “will potentially conflict with confidentiality and attorney-client privilege provisions in a number of countries”.