Following Creative's announcement that it has filed a lawsuit against Apple for breach of patent over the iPod's user interface, Apple is counter-suing.

According to an article in the International Herald Tribune, "Apple claims Creative Labs infringes four patents in its hand-held digital players. The suit was filed in a Wisconsin District Court on May 15, the same day Creative filed a lawsuit and a trade complaint against Apple".

The speed at which Apple has responded implies that Apple was ready and waiting for such an action to take place.

The original order announced earlier this week by Creative seeks to prohibit Apple from engaging in sales, marketing, importation or sale after importation into the United States, or other infringing activities in the United States with regard to the infringing iPod and iPod nano products.

If such a ruling went in favour of Creative, it would signal the end of the iPod making it illegal to be sold in America.

A recent estimate suggested that every other MP3 player was an iPod with the company dominating the market with around 80 per cent share.