Neighbour dispute

[ASHLEY66]

My new neighbours have decided to plant a hedge to grow to 6ft high along the end part of our joint boundary fence. These are new build houses and were built with open country fencing as there is miles of open country side views. Unfortunately if they do this I will lose all the beautiful views as well as light and sun and will no doubt depreciate the value and/or saleability of my house. They promised they would never do anything to spoil my view but have clearly changed their minds. No more sitting in my lounge or garden watching the wildlife. Im fairly sure I cannot do anything but thought I'd ask for any feedback.

Thanks