The government is giving its strongest indications yet of a Commerce Commission study into banking after a record result in profits last year.

National's finance spokesperson Nicola Willis said Labour should confirm its approach now, after it voted down her proposal for a shorter select committee inquiry.

She said it was a good-faith, pragmatic suggestion for a more public investigation.

But the Commerce Minister, Duncan Webb, said the government was actively considering the commission's advice, and National's "quick and dirty" approach would let banks off the hook.

Māni Dunlop spoke to Kiwisaver provider Simplicity director Sam Stubbs.