Other networks are also reported to be in talks with Google. According to the Telegraph:

The two giants are discussing a wholesale access agreement that would become an important part of Google's planned attempt to shake-up the US mobile market with its own network. It is understood that Google aims to create a global network that will cost the same to use for calls, texts and data no matter where a customer is located.

Google aims to team up with Hutchison to provide a gateway into the UK, Ireland, Italy and other markets the company operates in. It makes sense for Google to select the Hong Kong company as a potential partner as Hutchison is actively pushing free roaming across Europe with Three UK (currently supports select countries).

Sources said Hutchison was a natural partner for Google in the plan, because it has also sought to eliminate roaming charges for Three customers. Google announced its plans to launch a mobile network last month. It will not build mobile masts but rely on wholesale deals to use existing infrastructure both at home and abroad.

It's expected Google will launch its own virtual network to pile pressure on America's mobile operators, much like the search giant is attempting with Google Fiber. The European Union is also working to abolish expensive roaming across the region, but should Google and partners be able to achieve free global roaming, it could shake up the mobile industry.

Sourece: Telegraph