Analysts say it is too early to gauge the full impact on the industry, but the short-term effect is expected to be severe.

The growing list of abandoned events include next week's Apple Expo 2001 in Paris and a Salomon Smith Barney technology, media and internet conference in Cannes, due to be attended by up to 500 executives today.

The California Dental Association has cancelled a 15,000-attendee conference in San Francisco, and Dell, the computer maker, has also postponed a customer conference in the city.

Peter Rigby, chairman of Informa, the UK business information group that organises 3,000 conferences a year, says there could be a 15-20 per cent fall in business across the industry. "That's just a guess at this stage," he said.

"We know from our experience of the Gulf war that many US companies banned international travel completely. We have to expect that this may be repeated and probably magnified."

Insurex Expo-Sure, the event and exhibition insurer, says events scheduled before last Tuesday would be covered by insurance. However, that will not apply to companies planning ahead for conferences.

"There will understandably be a reluctance to travel to and from the US as well as within the country even when and if travel gets back to a state of normality," said Paul James, claims director.

The impact on some local economies is likely to be severe. A third of the 17.3m visitors to San Francisco each year attend conferences.

For many, the destruction of the World Trade Center, a popular conference venue, is too fresh in the mind to consider flying off to an event. Risk Waters Group was holding financial technology conference with 65 delegates on the 106th floor of the North Tower when it was hit by one of the hijacked aircraft.

But for others, going ahead is an expression of defiance. Cantor Fitzgerald, the bond broker that lost 700 of its 1,000 staff in the World Trade Center, still intends to send representatives to a derivatives conference in Singapore next week run by Metal Bulletin, the specialist publisher which runs 65 conferences.

Tom Hempenstall, chief executive of Metal Bulletin, believes there is a greater determination among his US clients to carry on with international travel than there was at the time of the Gulf war.

The International Investor Relations Federation is pressing ahead with its annual conference in Vienna next week. "The unanimous decision was not only to go ahead with the conference, but to take this opportunity to demonstrate determination not to be intimidated by terrorism," it said.

The long-term impact on international conferences is difficult to predict. "A lot will depend on the American response and how protracted the engagement is," said Mr Hempenstall.

There is an expectation that some companies may use the disaster as an excuse to cut spending already squeezed by a slowing global economy. "My gut feel is it's a tightening of belts disguised as a fear of travel," said one analyst.

But industry veterans say the business has bounced back from serious downturns before. "It cannot persist for long," said Mr Rigby. "If it does, it would not be just an impact on information businesses, but a complete dislocation of world trade."

Additional reporting by Sarah Ross and Matt Leising in San Francisco

Back to business impact stories index