O2 owner Telefonica and Vodafone are aiming to rollout 4G faster by joining their mobile networks into one shared grid in the UK.

The mobile operators will pool their basic infrastructure to improve coverage and speed up the rollout of the forthcoming 4G service. The firms are planning to achieve two competing nationwide 4G networks up to two years ahead of Ofcom's requirement of 98 percent coverage by 2017.

See also: Broadband advisor.

Ronan Dunne, CEO of Telefonica UK said: "This partnership is about working smarter as an industry, so that we can focus on what really matters to our customers – delivering a superfast network up to two years faster than Ofcom envisages and to as many people as possible."

O2 and Vodafone will combine their networks into one jointly operated grid which will run their independent spectrums. The network will be made up of 18,500 sites representing an increase in sites of more than 40 percent for each operator.

Both companies have promised to achieve 98 percent of indoor population coverage across 2G and 3G by 2015.

Guy Laurence, CEO of Vodafone UK said: "It will create two stronger players who will compete with each other and with other operators to bring the benefits of mobile internet services to consumers and businesses across the country."

O2 and Vodafone intend to establish the joint network later this year pending the authorisation from Ofcom, with which discussions are already underway.