Aviva has said up to 800 jobs at its UK business are under threat as it continues to drive through cost-cutting measures.
The cuts will come as part of a strategic overhaul of the group conducted by executive chairman John McFarlane (pictured).
The review began on 8 May, the day chief executive Andrew Moss stepped down after shareholders protested over pay levels.
The insurer, which informed its 18,500 UK employees of the possible cuts yesterday, said last month it would reduce seek to reduce annual expenses by £400m by cutting the number of management layers within the group from nine to five.
"The vast majority of our employees will be placed into roles with little change. Up to 800 roles could be at risk, although in practice it will be fewer than this because of natural turnover, voluntary redundancies and redeployment opportunities within Aviva. There will also be some new roles in growth areas," the insurer said in a statement.
"We recognise this is a difficult time for employees and will do everything we can to support them as we continue with our consultation process."
Unite, the union, said Aviva should "come clean" on the precise nature of the job cuts.
"It is absolutely appalling that Aviva has consistently failed to disclose the total number of jobs being cut. It is time for the company to come clean on the numbers," said national officer David Fleming.
At the start of 2012 the group's fund management arm, Aviva Investors, announced plans to scale back its London-based equities desk and said 160 jobs would go from its global business.