Microsoft (NSDQ: MSFT), which on one hand started touting its ad client wins following its $6 billion aQuantive’s deal which closed six weeks ago, is on a quiet PR campaign to convince Internet companies, advertisers and regulators to oppose Google’s (NSDQ: GOOG) planned $3.1 billion acquisition of DoubleClick, reports WSJ. PR firm Burson-Marsteller has been pitching on what it said were the dangers of the deal, including framing it as part of a larger discussion of “fair and free competition” in Internet-search and privacy rights of consumers.

In Europe it has launched i-comp.org, though the site is not reachable as of writing this…the PR firm did not disclose previously that it was working on behalf of Microsoft. Also, senior Microsoft executives have been urging executives at Time Warner (NYSE: TWX) and AT&T (NYSE: T), among others, to speak out against the deal, the story says.

Observer UK, which first broke the story, got the e-mail from the PR firm: The email asks companies to join a new organisation - Initiative for Competitive Online Marketplaces - which in the next few weeks will make a series of announcements on Google, internet privacy and copyright.

Meanwhile, MSFT’s aQuantive has tied up with Associated Press Online Video Network’s news distribution system and now allows affiliate sites to place local ads into their online video feeds. Microsoft said 20 publishers have switched from other ad serving providers or solutions to the Atlas Publisher Suite in the wake of the aQuantive deal, including SmartBrief, Reunion.com and Entrepreneur.com