The iPod Nano has proved popular with consumers

In the US, a similar case was filed in October after numerous complaints about scratched or broken screens.

The second lawsuit follows a large number of requests to be included in the action, said the case lawyer.

Apple admitted flaws with a small batch of Nanos, but denied that it was more likely to scratch than other iPods.

'Far-reaching response'

Both lawsuits argue that the problems with the screen on the Nano are due to a design flaw. They alleged that Apple was aware of the issue, but chose to ignore it in the rush to get the players into the shops.

It is alleged that the resin used on the Nano is much thinner than that used on other iPods.

"Apple's iPod Nano has sold in record numbers around the world, just as it did in the US," said Steve Berman, lead lawyer on both cases.

"The far-reaching response also reveals that this is not just a small problem or a bad batch of Nanos, but a defect in the overall design that should have been rectified prior to the release," he said.

Named UK plaintiff, Ben Jennings, bought a Nano in September. Despite efforts to protect it, he claims that within a week the screen was so scratched it was hard to read.

The initial lawsuit, filed on 19 October in the San Jose District Court, was kick-started by another disgruntled Nano customer, Jason Tomczak.

The latest lawsuit, filed in the US District Court for the Northern District of California, is being handled by Seattle-based law firm Hagens Berman Sobol Shapiro.

Complaints about the display on the iPod Nano led Apple to offer to replace defective screens on the music players within weeks of its debut in September.

At the time, Apple spokesman Tom Neumayr said the problems affected less than a tenth of a percent of the Nanos shipped.

As for the lawsuits, Apple says it does not comment on pending litigation.