The Federal Trade Commission is reportedly onsidering an antitrust investigation of Google's dominance of the Web search industry, Bloomberg reported on Monday.

Before deciding whether to launch such an investigation, the FTC is waiting for the Justice Department to decide whether it will challenge Google's planned $700 million purchase of airline ticketing software company, ITA Software Inc, Bloomberg said, citing the people.

Google has been also under investigation by the European Commission since last November.

Last week rival Microsoft filed a complaint with European antitrust regulators about Google's dominance of the Internet search market in the region.