The collaboration, announced Thursday, has been in a trial operation since December and will launch in full early this year. The Google search functions on China Mobile, the world's largest mobile carrier, will aim to facilitate access to content on the Monternet WAP portal, which includes news, ring tones, videos and games.

This is the second foray into the Chinese Internet market that Google has announced this week. On Tuesday, the Mountain View, Calif.-based company revealed it would invest in Shenzen Xunlei Network Technology, a video download service. It's no surprise that major U.S. companies like Google and Microsoft are turning to China as a growing hotspot for technology: recent research has shown that before too long China may surpass the United States as the country with the most Internet users.

But there's tough competition for China's red-hot Internet market. U.S. search engines like Google face a formidable rival in the Chinese search company Baidu. Baidu, meanwhile, has been expanding its own offerings, including a recently launched Japanese edition.