Berkshire Hathaway has warned its insurance arm could be further impacted from the economic fallout of COVID-19 after the division sank into a net underwriting loss of $US213 million ($292.6 million) in the third quarter.

Estimated losses and costs associated with the pandemic “negatively affected” the results of its commercial and reinsurance businesses, which had reported a $US440 million ($604.4 million) underwriting profit in the corresponding September quarter of last year.

“The potential effects of the pandemic may be further affected by future judicial rulings and regulatory and legislative actions pertaining to insurance coverage and claims that we cannot reasonably estimate at this time,” Berkshire Hathaway said.

“Our underwriting results for the remainder of 2020 and the first quarter of 2021 for certain business may be adversely affected from lower premiums attributable to credits granted to policyholders and where premiums are a function of the insured’s payroll.”

The insurance arm made a pre-tax underwriting earnings loss of $US291 million ($399.5 million) in the third quarter, compared with a year-earlier profit of $US581 million ($797.7 million).

Its commercial risk solutions business, Berkshire Hathaway Primary Group, swung into a pre-tax underwriting loss of $US126 million ($173.1 million), erasing the $US153 million (210.1 million) profit from a year earlier.

Berkshire Hathaway Reinsurance Group was also in the red, reporting a $US441 million ($605.6 million) loss compared with a $US52 million ($71.4 million) profit from last year.

Geico, the motor insurance business, managed to avoid a loss but its earnings fell to $US276 million ($379 million) from $US376 million ($516.4 million).

Overall insurance investment income moderated to $US1.01 billion ($1.4 billion) from $US1.48 billion ($2 billion).

Berkshire Hathaway’s overall net earnings for the third quarter nearly doubled to $US30.1 billion ($41.3 billion) from $US16.5 billion ($22.7 billion).