Following last week’s news that the European Union was considering jumping on the U.S. Department of Justice’s antitrust bandwagon, MarketWatch reports that The World Federation of Advertisers, (which claims to represent 55 national advertiser associations worldwide) said it has asked the European Commission to block the deal that would see the two Google and Yahoo! enter into an advertising partnership.

The possibility of a deal between the two search giants has sparked a formal inquiry from the Department of Justice regarding potential antitrust issues. While this review has been going on for several months, the European Union last week announced it was also looking into the deal and was considering an inquiry of it’s own. At the time Google said that while it was cooperating with both the EU and the DOJ, the deal would only affect Yahoo!’s North American sites and so, would have little effect on Europe.

According to MarketWatch, the Association of National Advertisers, a U.S. member of the World Federation of Advertisers, voiced its own concerns about the partnership ealier this month, claiming it would, “likely diminish competition."

Executive Vice President of Yahoo! Hilary Schneider replied to the letter assuring them the deal was going to do no such thing and Yahoo!’s intention was to use the deal to invest more in its own business.

"This is exactly the opposite of our business goals in pursuing this agreement," Schneider said. "The sponsored search connection to Google should ultimately shrink, not grow, over time — because we are focused on growing our own business, NOT Google’s."

When the deal was first announced, critics labeled it a scapegoat to escape takeover talks with Microsoft.