The company, part of Hong Kong group Hutchison Whampoa, had hoped by the end of the year to deliver handsets for third-generation, or 3G, services.

We can't be certain that these handsets will be on sale by the year end

Hutchison 3G

But it has now said it "can't be certain" of meeting this target because of difficulties encountered during the trials.

The news coincides with new research suggesting that picture messaging could also be slow to take off in Europe.

The author of the research, Strategy Analytics, warned that high handset prices and poor communication between different phone networks remain key barriers to success.

Picture messaging is seen as a vital stepping stone to 3G services, by whetting customer appetite for more sophisticated mobile services.

Hold up

Hutchison 3G said it was working on "a number of minor elements" before being able to give a definite launch date for the sale of its new phones.

"We can't be certain that these handsets will be on sale by the year end," said a spokesman for the group.

"We want to make sure that our customers get 100% service before we launch."

News of the delay comes despite the group insisting that it would have paying customers in the UK and Italy by the end of the year.

Picture of health?

Strategy Analytics meanwhile suggested that costs and poor network issues were critical to the success of picture phones.

The research group's survey of global mobile camera phone sales found that the leading market so far was the Asia Pacific region, with 9.2 million handsets sold during the first nine months of 2002.

Within that region, Japan and Korea were the biggest markets by far.

Western Europe came a distant second with just 200,000 handset sales over the same period.

Pricey handsets

Strategy Analytics said the new phones' high price tag - around $300, despite manufacturer subsidies of up to $400 a handset - was a "huge barrier" to lifting sales.

It added companies that can drive down the costs fastest will win the greatest market share.

Average handset prices need to fall to between $100 and $150 in order for the new technology to penetrate the mass market, the research found.

Strategy Analytics added that Nokia had an early leadership position in Western Europe with the launch of its Nokia 7650 phone earlier this year.

However, demand for the Nokia 7650 has been "moderate" so far this year.