O2 customers in London could experience faster mobile internet browsing after the operator switched to a new 3G network in the area.

O2 said the new network now uses the 900MHz spectrum, following Ofcom's announcement in January that operators can use the 2G spectrum to offer 3G services.

"This 3G900 switch-on is the latest in a series of network enhancements," said Nigel Purdy, chief technology officer at Telefónica O2 UK.

"We've acted quickly to bring the benefits of 3G over 900MHz spectrum to our customers and we're thrilled with the results. Quite simply, on O2's network, more customers can use more data, and experience it quicker."

O2 says the 3G over the 2G spectrum is already available in Leeds, Birmingham and Manchester, while it will be rolled out in other locations across the UK throughout the year. The network also said it will run alongside existing 3G spectrums and will ensure 50 percent more capacity is possible.

"Our strategy is to intelligently layer our network to give our customers connections to 2G, 3G, HSPA+, LTE and Wi-Fi," said Purdy.

The new 3G service can be used by any handset that's compatible with UMTS/HSPA 900MHz including Apple's iPhone 4 and the iPad 2.

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