Aviva and pensions company Friends Life are to merge in a £5.2bn deal that casts uncertainty over hundreds of UK insurance jobs.
Mark Wilson, chief executive of Aviva, admitted there will be job cuts as a result of his company's takeover of Friends Life but refused to confirm recent speculation that as many as 2,000 could go.
The deal with Friends is the biggest in the industry since the merger of CGU and Norwich Union created the company now known as Aviva in 2000.
If the takeover is backed by shareholders and goes ahead as planned by next spring, Aviva will become the UK's leading insurance, savings and asset management business by number of customers.
Aviva employs around 28,000 staff worldwide including 12,000 in the UK - York, Norwich, Sheffield and Glasgow - while Friends Life has 3,500 staff largely in offices in London, Manchester, Bristol and Salisbury.
There is no overlap between Friends and Aviva's general insurance arm.