The ANZ Bank is under fire for trying to reduce workers' hours despite posting a healthy profit from its New Zealand operations.

ANZ Bank's half year cash profit has increased 5% to $3.6 billion.

It's attributing that to solid growth .

Its New Zealand operation lifted profit 3% to $877 million.

First Union says ANZ is proposing to reduce the number of full time positions.

Spokeswoman Tali Williams says this is not acceptable from a bank that has just announced such impressive financial result.

"We believe the workforce base should be growing instead of shrinking. At the Whangarei branches they're proposing to reduce the number of full time positions and reduce people's hours of work."

The Bank's group result is slightly ahead of the four percent rise analysts had expected.

In contrast, rival Westpac yesterday unveiled a flat $3.7 billion first half cash profit, which was $100 million below market expectations.