The company announced that there would be 170 job losses at the offices.

These would be taken from a pool of 388 staff.

Workers affected are mainly lower-grade claims and customer service personnel, but postal, IT and 30 per cent of management level staff are also in the firing line.

Nationally, the company wants to cull 870 jobs.

Alan Wood, general secretary of the Union of Finance Staff, said it was locked in negotiations with the firm.

He said: 'We've started a consultation to try and reduce the number of those affected. We're looking at ways we can let go those who want to leave, and allow those who want to stay to remain in place.

'We want to offer people a chance to take a redundancy package, which would vary according to age and number of years worked. Whiteley is bigger, but in proportionate terms it's taking the same hit as the rest of the country. We want to see it reduced, especially on the compulsory redundancy front.'

The Whiteley office is Zurich's largest UK operations centre.

It employs 1,313 staff working in insurance, as well as another 232 employees.

Spokeswoman Wendy May said: 'What we always do is put more people at risk than we need to, because if you've got two people doing similar jobs, you can't pinpoint who will go. If people don't express a preference to leave, there will be a selection process based on people's experience worked out over the next few months.'

The firm said the process would end by September 3.