The ANZ is the parent company of ANZ in New Zealand.
In February last year a judge ruled that late payment fees charged by the ANZ in Australia on credit cards were exorbitant.
The class action was taken on behalf of more than 43,000 customers who claimed they had been charged excessive fees for years.
In some cases the fees were 70 times the cost to the bank of administering late payments.
But the judge also ruled in ANZ's favour by dismissing claims that other types of bank fees were illegal penalties.
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The case has since been appealed.
Hooker said he expected a decision to be made by the Australian Federal Court soon but there was no specific timeframe.
"These sorts of decisions take a while."
Until then the New Zealand cases had been stayed.
Hooker said the outcome of the Australian case would not necessarily determine what happened in New Zealand as New Zealand had its own laws and court process. But it made sense to wait.
Hooker said he had yet to file court documents against the ASB but he planned to do so once he had enough resources in place to gather the information together.
The banks have previously said they would vigorously defend any action taken.