?Katrina is a big loss and will probably be a market-changing event,? said Ron Pressman, chief executive of GE Insurance Solutions, the insurance unit of the giant General Electric Co.

Katrina could have the same transforming impact on insurers and reinsurers as the World Trade Center attacks, Pressman said. ?I think the impact of Katrina could be on the same level as 9/11,? he said.

?9/11 was an industry-changing event, as it focused the industry?s ? and arguably the world?s attention ? on the impact that terrorism could have and exactly how much damage could be done,? Pressman told Reuters on the fringes of a presentation in Monte Carlo.

?It also focused attention on the poor underwriting that occurred in the late 1990s and what needed to be done to change that.?

Asked whether rates needed to go up in the wake of the hurricane, which slammed into the US Gulf Coast wreaking massive damage, Pressman said the reinsurance industry?s record of delivering single-digit returns ?is simply not acceptable.?

He said, ?the results show a self-evident need to tackle the underlying technical underwriting to address that.?

Pressman said his company would probably issue an estimate of its claims to Katrina in mid-October. It is basing its assumptions on an insured loss estimate toward the upper end of experts? assessments.

?We are looking at this event in the range of $40 billion to $50 billion,? Pressman said.

Reinsurers and insurers are gathered in the Mediterranean resort to begin discussion of the cost of annual risk cover for next year.