Ace has reported second-quarter net income of $US942 million ($1.28 billion), up 20.8% on the corresponding period last year.

Gross written premium was up 8.3% to $US6.5 billion ($8.81 billion), and net investment income gained 1% to $US562 million ($761 million).

The property and casualty combined operating ratio moved to 87.7% from 87.5%, and pre-tax catastrophe losses grew to $US124 million ($168 million) from $US80 million ($108 million).

For the first half, net income was up 7.2% to $US1.62 billion ($2.19 billion).

The Zurich-based global insurer has agreed to buy US-based Chubb Corporation for $US28.3 billion ($38.34 billion) – believed to be the largest deal between two insurance companies.

Ace Chairman and CEO Evan Greenberg says the Chubb announcement was the “highlight of the quarter”.

“We are moving quickly and the senior leadership of both companies has formed teams that are already engaged in integration planning,” he said.

Ace shareholders will take 70% of the new company, which will operate under the Chubb name.