Creative Technology has asked a US court to block sales of Apple's iPods, claiming they violate one of Creative's US patents.

Creative on Monday also asked the US International Trade Commission to investigate whether Apple has violated US trade law by importing the players into the US, a move that eventually could halt iPod sales in the US.

The lawsuit asks the court to stop Apple from selling iPods and seeks unspecified financial damages. It was filed Monday in the US District Court for the Northern District of California.

Creative claims to have invented the user interface software used by most portable digital media players, including the iPod. This invention is protected by a 2005 patent entitled 'Automatic Hierarchical Categorization of Music by Metadata', (US Patent number 6,928,433) Creative said.

The company calls this patent the 'Zen Patent'.

An early entrant to the digital music player business, Creative sells a line of music and video players, called Zen, that competes with the iPod. The company, based in Singapore, is also known for its line of Sound Blaster audio cards.

Apple representatives were not immediately available to comment for this story.