The proposed legislation will form a new super-regulator, the Financial Markets Authority, a single body taking on regulatory functions from the Securities Commission, NZX and the Government Actuary. The bill will give the FMA the ability to enforce duties of market participants when it's in the public interest to do so.

"This is a significant new provision which the Securities Commission does not currently have," Power said.

"This bill will enable the FMA to have the power to exercise a person's right to bring a civil action against a financial markets participant, where it considers this to be in the public interest."

In May, the Securities Commission told investors in failed finance companies they could demand a refund plus interest from the investment vehicles, though they would not receive any help from the regulator.

The bill will also tighten up KiwiSaver regulation to ensure fund managers are primarily responsible for the accuracy of their investment statements and advertisements, and will demand trustees be responsible for supervising managers.

Finally, the bill will introduce a new layer of oversight to auditors, which have previously been self-regulating. The FMA will act as an independent watchdog on the Institute of Chartered Accountants, which will continue to monitor the auditors.