Quote:
" No person may participate in a gathering in the Tier 2 area which—
(a)consists of two or more people, and
(b)takes place indoors"
[Section 1(1), Schedule 1, The Health Protection (Coronavirus, Local COVID-19 Alert Level) (High) (England) Regulations 2020]
There is a relevant exception, as follows
"Exception 1 is that all the people in the gathering—
(a)are members of the same household, or
(b)are members of two households which are linked households in relation to each other"
[Section 4(2), ibid].
So, unless you and your friend are from 'linked households', you can't meet up at The Ritz.
To form 'linked households', at least one of the households must have only one adult in it and neither household can be linked to any other household. Once a 'link' has been formed, neither household can then 'break' that link and form a new link with any other household.
The Ritz won't cancel bookings for two people, as they've no way of knowing whether the customers will be coming from the same households (or from 'linked' ones).