Berkshire Hathaway has been hit by a $3.8bn writedown on its investment in Kraft Heinz, in an acknowledgment of the trouble Warren Buffett has had with his landmark 2015 consumer goods industry deal.

Berkshire said the 12 per cent quarterly decline in insurance underwriting profit stemmed primarily from reinsurance businesses and some smaller insurance businesses. Geico, its best-known insurance business, saw pre-tax underwriting profit rise 2 per cent, as a 5 per cent increase in premiums offset a smaller rise in accident losses.