Software giant Microsoft will apparently be hit with a hefty fine by European Union (EU) anti-trust regulators on Wednesday, for breaking the promise which it made with the regulators to end an anti-trust investigation into the company's controversial practice of denying a choice of Internet browsers to the users of its Windows software.

According to the information shared by unidentified sources aware of the proceedings, Microsoft faces fine in Europe for failing to keep its promise of offering the users of its Windows system a choice of rival Internet browsers.

It was in 2009 that Microsoft worked out an anti-trust settlement with the European Commission officials; and, as a part of the settlement deal, promised to give Windows users in Europe a choice of Web browsers, rather than pushing them to its own Internet Explorer.

However, Microsoft failed to offer users such a choice for over a year; and apologized for it in July 2012, saying that the failure resulted from a technical issue which it had not noticed. It then updated its Windows 7 and Windows 8 software to offer browser choice to European users.

With Europe's antitrust chief, Joaquin Almunia, charging Microsoft with failure to live up to the antitrust agreement in October last year, the company now faces the likelihood of a hefty penalty by EU antitrust regulators, for its non-compliance with the terms of an antitrust settlement.