In Scotland the equivalent regulations are The Health Protection (Coronavirus) (Restrictions) (Scotland) Regulations 2020 which closely mirror the English regulations.
The relevant section is 4(9):
(9) A person who is responsible for a crematorium or burial ground must ensure that, during the emergency period, the crematorium is closed to members of the public, except for funerals or burials where reasonable measures are taken to ensure that a distance of two metres is maintained between every person on the premises of the crematorium during the funeral or burial (other than between two members of the same household, or a carer and the person assisted by the carer).
I can confirm that this regulation applies to crematoriums only (and in some situations where crematoriums include burial grounds within their premises). The regulation does not generally extend to the closure of burial grounds to the public.