The European Commission will hit Microsoft with even bigger fines for failing to honour the anti-trust ruling against it.

According to a well-placed source, the software giant will now be charged €3 million per day - a 33 percent increase on the previous €2 million per day if it fails to comply with the EU's ruling from this point on.

Microsoft will be charged next week at the old rate for the period 15 December to the present day, amounting to €400 million. From that point on, if Microsoft continues to fail to comply with the Commission's ruling, it will be punished even further with the new rate.

As part of the 2004 ruling against Microsoft, the company was ordered to reveal technical information about its Windows operating system to rival software makers. Withholding the information amounted to an abuse of the dominance of Windows, the Commission ruled.

Microsoft has continually argued that the Commission’s demands are not clear. Last quarter, it said it finally understood what the Commission was looking for, following an oral hearing with the Commission, competitors and Neil Barrett, the monitoring trustee overseeing Microsoft’s compliance.

Last week it said it is working hard to meet a 18 July deadline for the final submission of the technical information. It claims the deadline was set by the Commission, the monitoring trustee, and Microsoft itself. However, the Commission denies it had anything to do with setting the deadline. "There was no joint setting of deadlines. There was no agreement on the timetable," someone close to the Commission said.

The Commission will take at least two months to assess the final installment of technical information. If it is deemed satisfactory, the few days between Wednesday and the final submission of the technical information will be waived and the Commission will not impose the higher fine.

"The Commission doesn’t want to fine Microsoft again. It wants the fine for the period from December 15 to be a sufficient deterrent," our source said. But he stressed the possible need for a greater deterrent. "The Commission has no guarantee that the information submitted on July 18 will be adequate. It will have to look at it and if it isn’t enough, then the increased daily fine will be applied," he said.

Neither the Commission nor Microsoft were immediately available to comment.