The new service will be delivered by Everything Everywhere, now rebranded as EE, to four UK cities during the testing phase.

While EE users will have access to the new service under that ‘superfast’ brand, current Orange and T-Mobile users will not, when the new service goes live.

London, Bristol, Cardiff, and Birmingham have now all received the 4G network which will now undergo stress-testing. Mayor of London Boris Johnson said: “We are now the city with the greatest 4G coverage anywhere in the world".

4G with potential speeds of 21Mbps is expected to have 98 percent UK population coverage by 2014.

The delivery of 4G services by EE has been widely criticised by the mobile operator’s competitors and the UK government has had to negotiate a one month pause on any legal action, due to the threat of delay.