Germany's economy minister says Google may have such a dominant market position that a break-up of the company "must be seriously considered".

Sigmar Gabriel says such a move would be the "ultima ratio," or last resort, in an effort to prevent the Internet giant from systematically crowding out competitors.

Mr Gabriel's comment in an op-ed for German daily Frankfurter Allgemeine Zeitung comes a day after 400 companies submitted a competition complaint against US-based Google to the European Commission.

Mr Gabriel said corporate break-ups had previously been necessary in the electricity and gas supply industries to prevent a single company from abusing its dominant position.

He says his ministry would look into whether new rules for regulating Internet platforms are necessary before doing anything else.