The South Downs will be exempt from an expected change in planning laws, which could have seen hundreds of new homes built without planning permission.

The Government is set to announce that redundant farm buildings can be converted or demolished to create up to three houses without planning permission.

With more than 900 commercial holdings within the South Downs National Park, the new legislation could have had a major impact before the exemption ruling following concerns raised by park bosses and environmentalists.

Trevor Beattie, chief executive for the South Downs National Park Authority, said: “It is great news that the Government has listened to our concerns and agreed that National Parks like the South Downs are precious green spaces which should be exempt from these plans.”