Member States shall take the necessary measures to ensure that:

(a) any laws, regulations and administrative provisions contrary to the principle of equal treatment are abolished;

(b) any provisions contrary to the principle of equal treatment which are included in individual or collective contracts or agreements, internal rules of undertakings, rules governing profit-making or non-profit-making associations, and rules governing the independent professions and workers' and employers' organisations, are or may be declared, null and void or are amended.