BEIJING - China's anti-trust authorities have approved Google Inc.'s acquisition of Motorola Mobility Holdings Inc. with conditions, clearing the regulatory barrier for the search engine giant to grow its mobile business in a market with the world's largest number of Internet users.

The Ministry of Commerce (MOC) said in a statement on its website Sunday that to win the approval, Google shall fulfil obligation to keep its open-source Android model on a free and open basis.

The MOC ruling came almost eight months of two extensions of an anti-monopoly review of the acquisition since Google and Motorola Mobility submitted a collective application in China last September.

Google announced last year that it would buy Motorola Mobility, the Illinois-based maker of mobile devices and other hardware, for about 12.5 billion U.S. dollars.

During the review period, the MOC found that the merger may have an effect of excluding or limiting competition in the Chinese smart mobile operating system market.

Google made commitment to the MOC that it will continue to license the use of Android platform on a free and open basis and treat all equipment manufacturers in a non-discriminatory way.

After the acquisition completes, Google shall continue to observe Motorola Mobility's obligations on patents in its currently fair, reasonable and non-discriminatory manner.

The MOC said it could monitor the market situation of China's smart mobile operating system after the five-year term due and determine future moves after assessment.

According to the MOC statement, Google should submit a report to the MOC every six months within the five-year term.