BRITAIN’S biggest insurer has revealed the extent of its exposure to US banking groups Lehman Brothers and AIG.

Aviva, which owns Norwich Union, said it had a £148m debt exposure to AIG, which was rescued in a £47.2bn bail-out by the US Government yesterday, and a £270m exposure to Lehman Brothers, the US investment banking group that collapsed on Monday.

Other firms to outline exposure to Lehman included Friends Provident, with £18m debt exposure to Lehman, and Old Mutual, which said its debt exposure to Lehman was “not material”.