Microsoft CEO Steve Ballmer has threatened to walk away from the $44.6 billion bid for rival Yahoo as the two companies continue to parry on the deal. Speaking at a conference in Milan on Wednesday, Ballmer said that Microsoft is "prepared to move forward without merging with Yahoo."

This comes days before Microsoft’s Saturday deadline for Yahoo to accept the deal before Microsoft goes ahead with a proxy battle to surpass the board and go directly to Yahoo’s shareholders. Speaking of the deadline, Ballmer said "We’ve sent them a letter that says, ’it’s a good price; please let us know. If you don’t let us know, maybe your shareholders will think it’s a good price.’"

The comments now threatening to go ahead in the fight against Google without acquiring Yahoo is a deliberate move by Ballmer to rattle Yahoo shareholders and remind them that there’s a significant premium on the share price sitting on the table, and it’s up to Microsoft to decide if it wants to simply walk away or not.

Meanwhile Yahoo management is continuing to root around for ways out of the merger, including the proposed merger with AOL and a deal with Google itself to display Google ads alongside Yahoo ones.

If the Yahoo board does not accept the deal by Saturday then it is more than likely that Microsoft will move ahead with the proxy battle rather than pull the deal.