The South Downs National Park is set to get improved mobile phone signal following the signing of a “landmark” deal.

EE, O2, Three and Vodafone, which make up the Mobile Operators Association, have teamed up with National Parks England to sign the government-backed accord.

The agreement pledges to bring “high quality connectivity" to the country’s 13 national parks while ensuring minimal impact on the environment.

Angie Blowman, from the South Downs National Park Authority, said: “This agreement will make it possible for South Downs communities to get the consistent and high quality mobile connection they need at the same time as protecting the precious landscapes for which the National Park was designated.

“We look forward to working with the mobile operators in order to achieve this.”

The deal is intended to tackle so-called “notspots” – areas where there is little to no mobile coverage.

National Parks are notoriously bad for mobile signal given the terrain and large number of stone buildings which radio waves struggle to penetrate.

Although there are no specific measures in place for the South Downs as yet, it is understood new masts could be built.

The accord states new masts would be shared between networks and designed to blend in with the surrounding environment.

Sarah Lee, head of policy at the Countryside Alliance, welcomed the agreement. She said: “National parks are treasured by the public for their natural beauty and iconic landscapes, but they are also living and working environments.

“We welcome this accord between National Parks England and the Mobile Operators Association and hopes it leads to better phone coverage in these environmentally sensitive areas in the near future.

“For far too long rural communities have been treated like second class citizens when it comes to mobile and broadband connectivity and it is time this digital divide is closed, so let's hope this accord ensures better coverage where it is needed most.”

The South Downs is the newest National Park having been established in April 2011. It stretches from Winchester in the west to Eastbourne in the east with more than 108,000 people calling the area home.

Communications Minister, Ed Vaizey MP said: "Our National Parks are areas of incredible beauty but they are also places where people live and work. They need access to the modern communications that many of us have taken for granted for years. The new agreement could make a real difference to those who live, work or visit our glorious National Parks."