Microsoft says it might delay the European Windows Vista introduction, stating it depended on the European Commission's antitrust requirements.
The European Commission responded sharply, saying it was "misleading to imply that the Commission could be the cause of delays in launching Vista in Europe."
Microsoft said in a statement it made concrete proposals to the European Union's executive Commission, responding to its concerns about new features in Vista.
"Once we receive the Commission's response, we will know whether the Commission is seeking additional product design changes that would result in delay in Europe," it said.
The Commission, the executive arm of the European Union, had a different perspective.
"It is not up to the Commission to give Microsoft a green light before Vista is put on the market; it is up to Microsoft to accept and implement its responsibilities as a near-monopolist to ensure full compliance with EU competition rules," a spokesman said.