The videotaped pre-trial testimony, showing Mr Gates jousting with government lawyers could be used as early as Thursday.

The ruling came in the second week of the landmark lawsuit, in which the federal government and 20 states are accusing Microsoft of using its monopoly in personal computer operating systems to try to squeeze out its competitors.

In the tapes, Mr Gates is said to discuss his fears that Netscape's Internet browser, together with the Java programming language that does not need the Windows system, threatened his lucrative business.

The government contends Microsoft made an illegal offer to Netscape to divide the Internet browser market, so that Microsoft had the Windows market and Netscape had the rest.

Gates's objections

Lawyers representing Mr Gates originally objected to the tapes being played, which are likely to be rebroadcast on the nation's television networks.

The lawyers argued that if so many hours were to be used, the US Government must count Mr Gates as a witness and give up one of its other 12 witnesses.

District Judge Thomas Penfield Jackson said Mr Gates was so important that "a witness of equivalent significance in this case doesn't immediately come to mind."

He invited Microsoft to offer another witness, if it can justify adding one.

Microsoft lawyer John Warden said he had no objection.