Westpac Banking Corporation is poised to axe more than 400 jobs and send another 150 offshore in the latest round of job cuts at the big banks.
Australia's second biggest bank briefed workers about the 410 job cuts and positions it will relocate to India as part of a group-wide restructure.
"We are commencing consultation with a number of our employees around changes to Westpac," a Westpac spokeswoman said.
The Finance Sector Union (FSU) said 150 positions would be moved to Bangalore, India, and it feared more cuts were on the cards.
The roles affected are mostly back office, non-executive support roles, but there will be a decline in the bank's overall standard of customer service, FSU national secretary Leon Carter said.
"They're saying this will be the most significant announcement they'll make this year but there's no guarantee that it's the last one," Mr Carter said.
"Westpac continues to make a multi billion-dollar profit and has the capacity, and we say the obligation, to invest in and protect Australian jobs not continue to sacrifice them on the alter of profit."
Westpac's acting head of Australian financial services Peter Hanlon told The Australian's website that the cuts were necessary due to the slowdown in business and consumer activity, as well as the lull in housing credit demand.
The bank will shift 150 jobs to its third party provider in Bangalore, along with 28 IT management roles in its wholly owned BT Financial Group and Westpac Institutional Bank.
Workers in India are usually paid between one-third and a half the wage of Australian workers in comparable jobs.
Westpac also is reviewing all business units excluding its New Zealand operations.
Prime Minister Julia Gillard said that despite the job cuts at Westpac, Australia's financial services sector had a bright future.
Ms Gillard said the growing middle class in China, India and other regional countries would ensure a strong future for financial services.
"That burgeoning new middle class will want sophisticated financial services that can be provided by us right here in Australia," she told reporters.