The insurance firm said last week that £300m of the planned savings would come from its UK IT operations during a two-year restructuring programme.
Seán Egan, chief information officer at Norwich Union, said the completion of major IT projects and a programme to consolidate the firm's systems meant that it no longer needed to devote as many resources to IT.
"A number of significant projects, such as the integration of RAC into Norwich Union, are nearing their natural end, and we therefore no longer need to maintain or upgrade old systems and services," he said.
"We are also in the process of transferring all administration onto a single platform across the business, which will reduce the number of IT systems we use."
The cutbacks will affect roles in IT development, maintenance and infrastructure services across Norwich Union and motoring services group RAC, which the insurer bought in 2005. Project management and business analysis roles supporting projects will also be lost.
The company said it hoped to find some staff alternative roles within the Aviva group. "However, due to the specialist nature of many roles, it will not be possible to redeploy all staff, and it is expected that there will be redundancies.
"We are operating in an increasingly changing environment and these changes will achieve greater effectiveness across our IT operations," said Egan.
The decision follows a review of IT across the business. The affected staff are based mainly in Norwich and Perth.
The company said that although it was never possible to rule out any further impact on jobs, this announcement marked the completion of its current plans.
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