Apple Inc. is pulling away from an annual trade show dedicated to celebrating its products, announcing Tuesday that chief executive Steve Jobs won't be delivering the keynote address at the annual Macworld show in January.

Apple also said 2009 would be the last year exhibiting at the Macworld Expo, a multi-day gathering of enthusiasts of products held in San Francisco and organized by the IDG technology media group.

Jobs has frequently used the Macworld address to make key company announcements about new products. In 2007 he stole the thunder of the concurrent Consumer Electronics Show when he gave the first sneak preview of the iPhone, and announced the ultra-thin Macbook Air at the last show.

Apple said Philip Schiller, a marketing executive, would deliver the keynote speech instead of Jobs.

The trade show, begun in 1985, dates back to when Apple was known for its computers and software and was struggling to compete with a host of competitors running Microsoft software.

Since then, however, Apple has found success with its iPod digital music players, sleeker laptop computers and its popular iPhone handheld device.

Apple said it was abandoning the trade show because it had other methods of communicating to its customers, such as its retail outlets and its iTunes online store.

Piper Jaffray analyst Gene Munster said the move could mean that Apple doesn't have a big product to unveil this year, but it also fuels speculation that Jobs could be having health problems. In 2004 Jobs recovered from a treatable form of pancreatic cancer.

"I think that Apple could have done a lot to have made it so people wouldn't speculate about Steve Jobs's health," said Munster.

Apple shares opened Wednesday at $91.03 US after closing Tuesday at $95.43 US, a drop of about 4.6 per cent.

With files from the Associated Press