Google has been accused by the European Union of abusing its dominance to lessen competition in the advertising realm, threatening to break up the business.

According to the EU, Google favours its own advertising program over those of its rivals, allowing it to dominate the supply chain and charge excessive fees for its own services.

“The commission’s preliminary view is therefore that only the mandatory divestment by Google of part of its services would address its competition concerns,” Margrethe Vestager, the EU’s competition commissioner, said.

Although she threatened that Google may be forced the sell off parts of its ad sales arm, this will likely take years to come into effect.

“Google remains committed to creating value for our publisher and advertiser partners in this highly competitive sector,” Dan Taylor, vice president of global ads at Google, said in a statement.

“The commission’s investigation focuses on a narrow aspect of our advertising business and is not new. We disagree with the EC’s view and we will respond accordingly.”