The country's largest bank ANZ was placed in a trading halt pending an announcement this morning.

The company has since resumed trading.

ANZ is due to release its six month result to March 31 today and is one of a number of major banks caught in a banking enquiry in Australia.

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It has already said it would take a $A50m ($53.5m) hit in its full financial year because of the Australian Royal Commission into Misconduct in the Banking, Superannuation and Financial Services Industry.

Andrew Bascand, managing director at Harbour Asset Management, said he expected to see some provisioning from the Australian banking inquiry come through in the half-year results.

He said lower lending growth combined with a rise in funding costs meant margins were likely to be under pressure.

"Banks are going to say it has been a fairly tough quarter."

He said the Australian banking inquiry would make it hard for the banks to increase mortgage rates out of cycle without a lift in the official cash rate.

ANZ's net profit for six months to March 31 last year was $869m.