Hanover, Germany  - Chancellor Angela Merkel of Germany and California Governor Arnold Schwarzenegger on Monday evening jointly inaugurated CeBIT, one of the top annual fairs in the technology industry.

Buyers were due to stream into the six-day event in the German city of Hanover starting Tuesday morning. The industry was jolted by forecasts of a sharp slump in worldwide sales of personal computers.

In a speech, Merkel affirmed plans to ensure that by 2015, three quarters of German households would have access to high-speed data links offering speeds of 50 megabits per second.

She appealed to owners of the radio-frequency spectrum to free these up for wireless data connections.

"We have a surplus of frequencies, but not every owner is willing to give them up," she said, demanding that licence-holders reach agreement so that the government could re-allocate the frequencies.

She also called on German operators of broadband optical-fibre networks to compromise and share.

Earlier Monday, Deutsche Telekom had announced it would rent out for the first time capacity on its costly optical-fibre data network to other telecoms companies.

The German telephone giant had originally refused to let business rivals pipe traffic through the high-speed VDSL network which it built in about 50 German cities, forcing them to route internet traffic through slower Telekom copper cables.

The European Union reluctantly agreed to Telekom having a headstart as sole user because of the enormous construction costs.

That network offers data transmission speeds of 50 megabits per second, twice the current top speed through copper. Germany has only a few other small optical-fibre networks, mainly run by municipalities. All the rivals normally lease one another's wires.

Timotheus Hoettges, chief executive of the company's T-Home division, said the move to rent out capacity on Telekom's VDSL network was voluntary and not in response to any regulatory pressure.

CeBIT exhibits computers, software and communications products, mainly for corporate and manufacturing buyers, but is also a showcase for personal computers, laptops and the new ultra-portable netbooks.

At the event this year, California has been declared "partner," an honorary status usually awarded to entire nations.

Schwarzenegger, speaking in both English and German to an invited audience, highlighted California's advanced computer technology.

Gartner, an analysis company based in Stamford, Connecticut, forecast Monday world sales of desk and portable computers this year of 257 million units, a decline of 12 per cent and the worst fall in the sector since it began.

It said sales in emerging markets would decline 10 per cent and in industrialized nations by 13 per cent.

However a German trade federation, Bitkom, offered a more upbeat forecast at a Hanover news conference Monday, suggesting the entire sector, including software and telecommunications products, would see worldwide sales growth of 3 per cent this year.

It said much of the sales growth would be scored in Latin America and Asia, but even Germany would manage 1.5-per-cent growth, helped by government purchases of new technology for schools and offices.

The data was compiled by European Information Technology Observatory, a Bitkom research unit based in Berlin.

Bitkom added that 55 per cent of its members in Germany said sales had held up so far, but nearly 60 per cent of Bitkom members expected the world recession to hit sales, while two-thirds were seeing signs of corporate clients cutting back or cancelling projects.

This year's CeBIT has suffered a 25-per-cent slump in exhibitor numbers to 4,300. In recent years, the Consumer Electronics Show held every January in Las Vegas, and Mobile World Congress, in February in Barcelona, have stolen some of its glamour as a gadget showcase.