A New Zealand banker defrauded clients of $13m to fund a lavish lifestyle of prostitutes, property and wine, according to local media.

Stephen Gerard Versalko, 52, was convicted of stealing NZ$17.8m from the clients of his employer, ASB Bank, and jailed for six years, the Dominion Post newspaper reported.

Court officials could not be reached for comment.

The biggest single employee fraud case in New Zealand came to an end after one of Versalko's clients saw a documentary on fraudster Bernard Madoff and saw similarities in behaviour.

Between 2000 and 2009 Versalko spent at least NZ$3.3m on prostitutes, NZ$4m on luxury properties, as well as more than NZ$300,000 on wine, along with cars and a boat.

One prostitute received NZ$2.5m over that time, and the bank is taking legal action to get property she bought with the money, media reported.

Like the high-profile Madoff, Versalko ran a so-called ponzi scheme using NZ$4.6m of the defrauded money from new clients to pay off earlier investors.

Versalko's victims were largely elderly women, living outside of New Zealand, who were led to believe their money was in high-return, government guaranteed investments.

The bank has repaid all the investors not only the amounts involved but also the interest they were promised.