Typhoon Jebi, which pounded Japan last week, looks set to hit the lower layers of the cat excess of loss treaties bought by the Japanese “big three” insurers MS&AD, Tokio Marine and Sompo Japan Nipponkoa.

The typhoon – which made landfall last week as a cat 3 measured by windscale - was the most powerful to have struck Japan in a quarter of a century.

In an early estimate, modeling firm AIR Worldwide has said insured losses from the storm were expected to be in the range of $2.3bn and 4.5bn.

The estimate includes insured damage to residential, commercial, industrial and agricultural property as well as auto losses.

However it excludes the cost of landslides, precipitation-induced flood as well as marine hull and cargo lines.

According to RMS, some of the biggest losses could result from the damage to Kobe and Osaka ports and “marine cargo damage could be substantial”.

As a result, sources have told this publication they are expecting the loss to exceed $5bn and perhaps climb as high as $6bn.

Infrastructure was badly affected by the typhoon. At Kansai International Airport, which serves the greater Osaka region, runway aprons, planes and terminal buildings were flooded by storm surge.

Adding to the problems at the airport, a tanker that had been anchored in Osaka Bay drifted out and caused significant damage to a two-mile long bridge which acts as the sole connection from the airport to the city of Izumisano.

Around 800 domestic and international flights have so far been cancelled, affecting nearly 60,000 people.

According to RMS, some of the biggest losses could result from the damage to Kobe and Osaka ports and “marine cargo damage could be substantial”.

One senior reinsurance CEO told Re-Insurance that he expects typhoon Jebi to be a “significant reinsurance loss”.

Japanese renewals typically take place in April each year.