New York  - US software giant Microsoft Corp Tuesday appealed a court ruling that could stop sales of Microsoft Word in the United States.

A Texas court last week ruled in favour of software company iSi, which accused Microsoft of copyright infringement regarding the creation of custom XML (Extensible Markup Language) documents.

The court awarded the small software firm damages of 290 million dollars and gave Microsoft until October 10 to stop selling Word products that let users create XML documents.

Microsoft said it has not infringed the patent and accused the court of several mistakes. It warned of problems should Word - and with it the whole Microsoft Office software package - be removed from the market.

XML is a common format for encoding documents electronically and is widely used in office programs such as Microsoft Office or OpenOffice. org. (dpa)