Microsoft is not ruling out a joint bid for Yahoo! with Rupert Murdoch's News Corp, it has been claimed

According to Reuters, a source familiar with the deal said that News Corp has been speaking directly to the company without involving Microsoft.

The Wall Street Journal reported last week about the two companies putting in a joint bid for the internet firm, and also claimed that Yahoo!'s board of directors has failed to reach a decision on their future.

Rumors of a merger with AOL, in negotiations with Time Warner, were also reported in the Journal. However, representatives for the four companies involved in proceedings have not commented on any deals to date.

Microsoft originally launched its $42 billion takeover bid in February. Chief executive Steve Ballmer gave a three-week deadline for Yahoo! to accept the offer on April 5th.

The firm rejected the ultimatum, claiming that it has been undervalued.