Race and nationality are not the same thing, of course. Americans, for example, are not one single biological race, but several. However, the Race Relations Act and the Race Discrimination Act apply to mistreatment of a person because of their nationality or ethnic identity, not just biological race. The only difference between, say, a Scotsman and an Englishman is accent, but if the Scotsman went to London and was refused a job because he's Scottish, that would be classed as racial discrimination.