Google's US$12.5 billion bid to buy cellphone maker Motorola Mobility has won approvals from US and European antitrust regulators, moving Google a major step closer to completing the biggest deal in its 13-year history.

Monday's blessings mean Google Inc just needs to clear regulatory hurdles in Chinese mainland, Taiwan and Israel before it can take control of Motorola Mobility Holdings Inc and expand into making phones, tablet computers and other consumer devices for the first time.

Google prizes Motorola Mobility's over 17,000 patents - a crucial weapon in an intellectual arms race with Apple, Microsoft and other rivals trying to gain control over smartphones, tablets and other mobile devices. Google unveiled the deal six months ago.

The deal will "enhance competition and offer consumers faster innovation, greater choice and wonderful user experiences," Don Harrison, Google's deputy general counsel wrote in a blog post.

Besides signing off on the Motorola Mobility deal, the Justice Department also approved two other moves in the mobile patent battles. The approvals cover the US$4.5 billion purchase of Nortel Networks patents by a group including Apple, Microsoft and BlackBerry maker Research in Motion Ltd and a separate Apple acquisition of Novell Inc patents.

The department ended its investigations after concluding the new patent owners won't try to drive up the prices of competing mobile devices by demanding exorbitant licensing fees. It said it was particularly concerned about key patents held by Motorola Mobility and Nortel.

Apple and Microsoft promised to license the Nortel patents on reasonable terms while Google's commitments on the Motorola Mobility patents were "more ambiguous," according to a statement from the department's antitrust division.