LONDON — A British court ruled on Friday that ethical veganism was a philosophical belief that should be protected against workplace discrimination, in a landmark decision sought by a vegan who claimed he had been unfairly dismissed from his job because of it.

The complainant, Jordi Casamitjana, argued that his employer, the League Against Cruel Sports, fired him after he raised concerns about his pension fund’s investment in companies involved in animal testing.

In addition to not eating animal products, ethical vegans reject all forms of animal exploitation, and usually refuse to wear wool or leather, or to use products tested on animals.

On Friday, Judge Robin Postle at the employment tribunal in Norwich, in eastern England, ruled that ethical veganism qualified under Britain’s Equality Act as a philosophical belief and that those embracing it were entitled to similar protection as those who hold religious beliefs.