Online advertising firm DoubleClick is reportedly set to be acquired by Google, although earlier reports indicated Microsoft closer to such a deal with the popular Ad firm.

The report comes from Wall Street Journal on Monday, claiming that as the acquisition price surpassed the $2 billion, Microsoft has been slow in responding with a counter offer. However, the negotiations are still in progress and no deal has been announced yet.

Microsoft, AOL and Yahoo have been also rumored to have negotiated a deal with DoubleClick in the past. But an acquisition from Google could further strengthen DoubleClick's position on web advertising.

Doubleclick has currently over 1500 clients including large companies such as Ford, AOL network and MySpace.