The bank workers' union Finsec wants the Reserve Bank to step in and prevent ANZ National from sending 500 jobs to India and for the Government to support such a move.
"The Reserve Bank can protect New Zealand jobs," said Finsec campaigns director Andrew Campbell.
"We are callingon the Reserve Bank to use all mechanisms it currently has and develop more if needed to stop this unnecessary attack on New Zealand workers and bank customers."
Mr Campbell said New Zealand bank customers should be protected from the risk posed by the proposal.
"If there is any failure of the operation in Bangalore, the impact on the bank's ability to operate, ensure customers' access to funds and meet their other requirements could all be in question."
Finsec also called for a change to Reserve Bank outsourcing policy by introducing a national interest provision, as the Government had done to the Overseas Investment Act.
Mr Campbell said the stability of the banking system was of huge strategic importance to New Zealand and needed to protected.
Finsec said last week 500 jobs would be lost but ANZ National chief executive Graham Hodges denied this and accused the union of sensationalising the situation.
"None of our staff need to lose their jobs," he said.
Work was moving to India but the bank was confident it could redeploy workers to alternative roles.
The bank employs 9600 people in New Zealand. In the past three years the bank has increased its workforce in New Zealand by 800.
It has about 33 per cent of the residential mortgage market, 40 per cent of the rural banking market and 35 per cent to 40 per cent of the business banking market.
It made a $1.04 billion profit in New Zealand in the year ended September, 2007.
