An Australian court has forced file-sharing network Kazaa to filter content available through its service to prevent music theft.

The company has ten days to do so, or must cease trading. The warning comes two months after Kazaa was ruled in breach of copyright by the Federal Court of Australia.

Kazaa's operators, Sharman Networks, had appealed against the decision, but Justice Murray Wilcox denied the appeal and told the company to comply with the order.

Wilcox said the labels are: "Entitled to have the benefit of a judgement in their favour. That is very important. Copyright infringement is occurring on an enormous scale at this moment."

The new filter uses 3,000 keywords selected by the record labels. It can also be updated on a fortnightly basis to target releases nominated by the labels.

The CEO of the Australian record label group, ARIA, Stephen Peach said:  "Today's decision is excellent news. The court has put an end to Kazaa's delay tactics on filtering and ordered them to get on with it if they wish to continue operating."

IFPI Chairman and CEO John Kennedy said:  "It is time for services like Kazaa to move on - to filter, go legal or make way for others who are trying to build a digital music business the correct and legal way."