The Housing (Preservation of Right to Buy) Regulations 1989

3.  The conveyance or grant shall include–

(a) such provisions (if any) as the qualifying person may require for the purpose of securing to him rights of way over land not comprised in the dwelling-house, so far as the landlord is capable of granting them, being rights of way that are necessary for the reasonable enjoyment of the dwelling-house; and

(b) such provisions (if any) as the landlord may require for the purpose of making the dwelling-house subject to rights of way necessary for the reasonable enjoyment of other property, being property in which at the relevant time the landlord has an interest, or to rights of way granted or agreed to be granted before the relevant time by the landlord or by the person then entitled to the reversion on the tenancy.