The path will be used by walkers, cyclists and horse riders on the popular Downs Link between Steyning and Shoreham.
It will run close to the River Adur, passing under the A283 road bridge and through a field on the north side of the road.
West Sussex County Council’s rights of way committee agreed at its meeting in County Hall on Tuesday that a path creation order should be made.
Speaking after the meeting, Cllr David Barling, who represents Bramber Castle, said there was very little discussion because everyone was totally behind the project.
In a report by Sue Hawker, director of communities commissioning, it explained there had been concerns for many years about the safety of the Downs Link crossing point on the A283 south of Bramber.
The new path would provide an alternative, safer route, but the existing uncontrolled crossing point would remain open for those who wanted to use it.
The alternative route will pass under the road bridge, through a field, across a ditch and through a wooded highway verge to rejoin the Downs Link at its existing crossing point.
It adds 970m to the length of the route, but it was felt the improved safety benefits would outweigh the additional length travelled.
The new route has the added benefit of providing a linking section in an accessible riverside route that is being developed for pedestrians and mobility scooters from Bramber.