Everything Everywhere, the combined entity of Orange and T-Mobile, has switched on its 4G network in four UK cities, so that the company’s engineers can begin live testing and systems integration in preparation for a commercial rollout, but customers of the existing brands will not have access to the new 4G services.

Last month, communications regulator Ofcom approved Everything Everywhere’s request to use its 1800MHz spectrum holding for next generation 4G services, which will allow it to roll out a Long Term Evolution (LTE) network several months before its competitors.

The LTE network will become available to consumers and businesses in London, Bristol, Cardiff and Birmingham in the coming weeks, and is expected to launch in 12 more cities – Edinburgh, Belfast, Derby, Glasgow, Hull, Leeds, Liverpool, Manchester, Newcastle, Nottingham, Sheffield and Southampton – by Christmas.

Further towns, cities and rural areas will follow rapidly, with 2013 population coverage to reach 70 percent, and 98 percent covered by 2014.

Orange and T-Mobile customers will not have access to 4G services when the network goes live. Instead, 4G services will be offered under a new brand name, EE, which the company is characterising as a “superfast” customer brand to stand alongside its existing brands.

Orange and T-Mobile customers with compatible handsets will have the option to upgrade to the new EE brand. Supported devices include the Samsung Galaxy S3 LTE, the Nokia Lumia 920 and 820, the HTC One XL, and the Huawei Ascend P1 LTE, E589 Mobile WiFi and E392 Mobile Broadband stick.

EE was not able to confirm whether the forthcoming iPhone 5, expected to be unveiled tomorrow, will be supported. However, Olaf Swantee, CEO of EE, said that the company would be “announcing more devices very shortly”.

Swantee said that the UK's digital backbone has become “as important as the roads, the railways and the airports”. He said that existing networks are too slow to meet current demand, and the advent of 4G would allow Britain to become “a more modern, connected country”.

The company will also offer fixed-line broadband services under the EE brand, which will be provided using BT's fibre infrastructure. Fotis Karonis, CTO of EE, told Techworld that this would allow EE to move away from being a simple mobile operator to become an “creative communications provider”.

EE did not offer any pricing information for either its 4G mobile or fixed-line broadband services, but Karonis said the intention was “to be really competitive and address the broader public”.

He added that, although Orange and T-Mobile customers will not have access to 4G services, they will benefit from ongoing investment in EE's 2G and 3G mobile network.

“We've invested quite heavily to support the growth and the quality of the network – developing the 2G network, putting huge investment into the 3G network, integrating the two together to make it fully seamless, adding all of this backhaul capacity. You need all of those ingredients to allow you to launch 4G,” said Karonis.

EE expects its new “superfast” brand to be particularly attractive to small and medium businesses and large enterprises. This is because, as employees become increasingly mobile, the reliability of the network becomes a major priority.

“The improvements that we have made over the last year by integrating the Orange and T-Mobile networks has given us the capability to offer business customers much wider coverage and better SLAs,” said Karonis. “We also have indoor coverage, and we study businesses' vertical requirements to provide end-to-end solutions.”

To support the launch of the new brand, EE is opening more than 700 branded stores across Britain’s high streets. The new EE stores – formerly Orange and T-Mobile shops – will serve customers of all three brands.

Britain has previously been criticised for being in the slow lane when it comes to 4G mobile services, trailing countries such as Angola, Azerbaijan and Uzbekistan. However, Ovum analyst Matthew Howett said EE's decision to cover London in its entirety from day one makes it “one of the most ambitious rollouts we have seen”.

Mayor of London Boris Johnson, who attended the press conference at London's Science Museum, welcomed the imminent arrival of EE's 4G network in the capital. “We are now the city with the greatest 4G coverage anywhere in the world," he claimed.