> (ii) which he cannot show to be justifiable irrespective of the colour, race, nationality or ethnic or national origins of the person to whom it is applied ; and
See also Article 1 of the International Convention on the Elimination of All Forms of Racial Discrimination:
> In this Convention, the term "racial discrimination" shall mean any distinction, exclusion, restriction or preference based on race, colour, descent, or national or ethnic origin which has the purpose or effect of nullifying or impairing the recognition, enjoyment or exercise, on an equal footing, of human rights and fundamental freedoms in the political, economic, social, cultural or any other field of public life.
Both "descent" and "national or ethnic origin" appear relevant here.
From 2010, written into UK law: https://www.legislation.gov.uk/ukpga/2010/15/section/9
> 9 Race
> (1)Race includes—
> (a)colour;
> (b)nationality;
> (c)ethnic or national origins.
From 1976 (over 40 year ago), written into the previous UK law: https://www.legislation.gov.uk/ukpga/1976/74/enacted
> 1 Racial discrimination
[...]
> (ii) which he cannot show to be justifiable irrespective of the colour, race, nationality or ethnic or national origins of the person to whom it is applied ; and