Legally, he cannot erect any fence over 2 m (6.6ft) without planning permission.
That 2 meter height would be taken from your garden not his.
You can refer this to the Local Planning department .
There is no right to light in a garden, only into buildings and even then, it would only be actionable if you had acquired the right to light or it was not excluded in your deeds and the light had been reduced by 50% into a room.
Legally, there is no right to review so if this obstruct your view, that is not actionable.
Can I clarify anything for you?
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