The insurers say the risk of a "perfect storm" causing vast damage to communities along the Atlantic coast has simply become too high since Hurricane Katrina obliterated New Orleans in 2005.

As a result, the country's largest home insurers, State Farm and Allstate, have decided not to seek new business along wide stretches of the US East Coast.

Tens of thousands of US homeowners may thus find it more arduous to obtain new insurance for coveted coastal properties in coming years.

The insurers point out, however, that beachfront property prices have skyrocketed in recent years, coastal populations have boomed and building codes in some areas are not vigorous enough.

State Farm, the United States' biggest home insurer, has decided not to write any new homeowner's insurance policies for coastal communities stretching south from Delaware to North Carolina, according to spokesman Dick Luedke.

"Our maxim is, we don't want to make new promises that would in any way compromise the promises that we have already made," Luedke said.

Allstate, the nation's second-largest home insurer, is also not writing new insurance policies for homeowners in some Maryland and Virginia coastal areas.

"We've looked at this ... to look at what our risk is on this coastline, and in some areas, it's just too great for us to insure anymore," Allstate spokeswoman Debbie Pickford said.

Allstate is also not issuing new homeowner policies for all five boroughs of New York, where millions of people reside just above sea level, and Long Island. It will also not seek new business for the entire state of New Jersey from February 5.

Both insurers, however, are continuing to renew existing homeowner policies and stressed that coverage is not being cancelled. Smaller companies, meanwhile, are continuing to seek new business.

The big insurers started rethinking their oceanfront exposure in the wake of the record-setting US hurricane seasons of 2004 and 2005, and especially after Hurricane Katrina ravaged the Gulf Coast city of New Orleans, Louisiana and Mississippi, killing over 1,000 people.

"All the risk-modeling professionals and all the risk-management specialists out there are looking 10 to 20 years down the road and saying, and scientific evidence, as well, and everyone is saying that you've got a perfect storm or catastrophes that could potentially affect the coastal areas," Pickford said.

Allstate had to swallow a loss of 1.5 billion dollars in the third quarter of 2005 due to Katrina and three other large storms as thousands of homeowners filed insurance claims.

Pickford said Allstate also needs to ensure it has enough cash on hand to meet potential damage claims.

Patricia Campbell-White, a real estate broker for the Re/Max Realty Group in the affluent coastal community of Rehoboth Beach, Delaware, says wealthy individuals are still buying multimillion-dollar oceanfront homes, and they are prepared to pay higher insurance premiums to live steps from the beach.

"Certain companies have shied away from writing policies for a number of years," Campbell-White said, adding: "I have not run into a situation where I have not been able to find a company to write a policy."

She said first-time buyers and those on lower incomes are likely to be impacted more by the big insurers' decisions than affluent families will be, and said that other insurers are still prepared to carry the risk of a coastal home.

Fears that another huge hurricane like Katrina or the so-called 1938 "Long Island Express" could lay waste to a densely populated coastal region have nonetheless triggered a new lobbying effort.

The big insurers have founded a new coalition, ProtectingAmerica.org, which is urging states and the federal government to establish emergency catastrophe funds.

The coalition's website features apocalyptic images of the aftermath of hurricanes and earthquakes, as well as satellite pictures of so-called super storms.

ProtectingAmerica.org wants insurers to be allowed to pay a portion of their property insurance premiums into emergency funds which could be used to repair mass storm- or earthquake-related damage.

The coalition is co-chaired by James Lee Witt, a former director of the Federal Emergency Management Agency, the primary US agency charged with responding to national disasters.

The hurricane-prone state of Florida already has such an emergency fund, with a threshold of 4.5 billion dollars.

In the meantime, the millions of Americans who live along the East Coast and the Gulf of Mexico have about six months' respite before the next hurricane season strikes.

The Atlantic hurricane season traditionally runs from June to November.

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