Despite fierce lobbying by Microsoft, Yahoo, and privacy advocates, European regulators today approved Google’s $3.1 billion purchase of DoubleClick, paving the way for the search giant to further move into the online display advertising market.

Those opposing the merger between Google, which has a huge market in text ads, and DoubleClick, which serves up graphical web banner ads, would help create a monopoly in the online advertising market. According to the EU’s competition committee, however, the deal isn’t a threat to competition because the companies are not competitors and Microsoft, Yahoo and AOL all offer credible alternatives for placing ads. This will no doubt increase the pressure on Microsoft to strike a deal for Yahoo to better compete in the growing Internet ad market.