With the EU looking to investigate the use of Google Adwords on Yahoo’s network in US and Canada the World Federation of Advertisers (WFA) has also presented the disagreements of various advertisers to the EU.

Although the deal would be isolated to the US and Canada, advertisers say it will have a global impact.

“We feel this deal between Google and Yahoo in North America will have a detrimental impact on how they compete with each other around the world — as they do today,” said WFA spokesperson Robert Dreblow.

This isn’t the first time advertisers disagreed about Google’s methods. The WFA was in staunch disapproval of the DoubleClick acquisition in 2007

Yahoo disagrees. “Although the World Federation of Advertisers did not seek any information from us about this agreement, we have made clear from the beginning that it will strengthen Yahoo’s competitive position in online advertising and will help to drive a more robust, higher-quality Yahoo marketplace for our advertisers, publishers and users,” said Yahoo spokesperson Tracy Schmaler. “Furthermore, advertiser demand will continue to drive prices — up or down — and advertising performance will drive that demand, not collaboration between Yahoo and Google.”

The major reason behind the disagreement stems from the amount of the PPC online advertising market that Google would control through Yahoo. Attorneys from both the US Association of National Advertisers and Microsoft have found that Google would control 90% of the PPC market. Microsoft’s attorneys testified before the US Congress in July that no single company has every controlled 90% of advertising in any market.