In a move that marks the Google-branded Nexus One smartphone’s head-to-head competition with the popular Apple iPhone 3GS, Google said in a March 16 announcement that its January-released handset will also run on the AT&T 3G network in the US, as well as Rogers Wireless in Canada.

While the original Nexus One model, which is still on sale, runs on the 3G network of T-Mobile, and the older, slower network of AT&T; the latest version of the handset supports the wide-ranging frequencies that AT&T uses for 3G.

Since Google sells the Nexus One as an ‘unlocked’ device – meaning that users can use it with a SIM card from most GSM operators round the world - and does not require a service plan for AT&T's 3G network.

The new Nexus One handset has Tuesday onwards been made available for sale from the Google Webstore. It is being projected that in case the smartphone can find purchase on the AT&T network, it will result in a more direct competition between Google and Apple.

However, as of now, the involvement of AT&T in the new Google Nexus One – which is based on the search engine’s latest Android 2.1, and features a speedy 1 GHz processor - appears to be almost negligible. The carrier is neither selling nor subsidizing the handset, which is available only from Google at its full price of $529.