Microsoft is gearing up for a hostile acquisition of Yahoo, with a formal announcement possible Friday, the Wall Street Journal reported.

"With the right circumstances it'll happen. Without the right circumstances it won't happen," Microsoft chief executive Steve Ballmer said in an interview with the Wall Street Journal Thursday.

Microsoft's board met Wednesday to discuss its next step for the deal, announced Feb. 1, which offered $44.6 billion for the Internet company. Yahoo rejected the offer, leaving Microsoft with the choices of walking away or attempting a hostile takeover. The report quoted people familiar with the matter in regards to the lean toward a takeover fight.

[ Keep up on all the twists and turns of this saga with our special report on Microsoft's bid to buy Yahoo ]

Ballmer also told Microsoft employees Thursday, "I will go to what I think it's worth if that gets a deal done," the report said.

Microsoft is also considering raising its bid, from over $29 per share, to $32 or $33 per share. Yahoo rejected that offer, stating that a fairer valuation is $35 to $37 per share. As Microsoft's own share price has declined since the February offer, the company would have to adjust its offer in order to reach the original terms of the deal, a mixture of cash and Microsoft shares.

Yahoo took its own steps Thursday, moving closer to an agreement with Google to begin carrying its ads, a deal that would bring Yahoo up to $1 billion more per year in revenue and make a Microsoft takeover more difficult.

Google, Microsoft, and Yahoo have not commented publicly on the above reports.