267. The State did not respond specifically to these arguments. 268. The Court has established that Article 1(1) of the Convention is a general rule the content of which extends to all the provisions of the treaty, and establishes the obligation of the States Parties to respect and ensure the full and free exercise of the rights and freedoms recognized therein “without any discrimination.” That is to say, whatever the origin or the form it takes, any conduct that could be considered discriminatory with regard to the exercise of any of the rights guaranteed in the Convention is per se incompatible with it.294 This State’s non-compliance, through any discriminatory practice, with the general obligation to respect and ensure human rights results in its international responsibility.295 Thus, there is an indissoluble connection between the obligation to respect and ensure human rights and the principle of equality and non-discrimination. 269. The principle of equal and effective protection under the law and of nondiscrimination constitutes an outstanding element of the system for the protection of human rights embodied in various international instruments296 and developed by legal doctrine and case law. In the current stage of the evolution of international law, the basic principle of equality and non-discrimination has entered the sphere of jus cogens. 294 Cf. Proposed Amendments to the Naturalization Provisions of the Constitution of Costa Rica. Advisory Opinion OC-4/84 of January 19, 1984. Series A No. 4, para 53. 295 Cf. Juridical Condition and Rights of the Undocumented Migrants. Advisory Opinion OC-18 of September 17, 2003. Series to No. 18, para. 85. 296 Some of these international instruments are: the OAS Charter (Article 3(l)); the American Convention on Human Rights (Articles 1 and 24); the American Declaration on the Rights and Duties of Man (Article II); the Additional Protocol to the American Convention on Human Rights in the Area of Economic, Social and Cultural Rights “Protocol of San Salvador” (Article 3); the Inter-American Convention on the Prevention, Punishment and Eradication of Violence Against Women “Convention of Belém do Pará” (Articles 4(f), 6 and 8(b)); the Inter-American Convention on the Elimination of All Forms of Discrimination Against Persons with Disabilities (Articles I(2)(a), II, III, IV, and V); the United Nations Charter (Article 1(3)); the Universal Declaration of Human Rights (Articles 2 and 7); the International Covenant on Economic, Social and Cultural Rights (Articles 2(2) and 3); the International Covenant on Civil and Political Rights (Articles 2(1) and 26); the International Convention on the Elimination of All Forms of Racial Discrimination (article 2); the Convention on the Rights of the Child (article 2); the Declaration on the Rights of the Child (Principle 1); the International Convention on the Protection of the Rights of All Migrant Workers and Members of Their Families (articles 1(1), 7, 18(1), 25, 27, 28, 43(1), 43(2), 45(1), 48, 55, and 70); the Convention on the Elimination of All Forms of Discrimination against Women (articles 2, 3, 5, 7 to 16); the Declaration on the Elimination of All Forms of Intolerance and Discrimination Based on Religion or Belief (articles 2 and 4); the Declaration of the International Labour Organization (ILO) on Fundamental Principles and Rights at Work and its Follow-up (2(d)); International Labour Organization (ILO) Convention No. 97 on Migrant Workers (revised) (article 6); International Labour Organization (ILO) Convention No. 111 concerning Discrimination in Respect of Employment and Occupation (articles 1 to 3); International Labour Organization (ILO) Convention No. 143 (ILO) concerning Migrant Workers (Supplementary Provisions) (articles 8 and 10); International Labour Organization (ILO) Convention No. 168 concerning Employment Promotion and Protection against Unemployment (article 6); the Proclamation of Teheran, the Teheran International Human Rights Conference, May 13, 1968 (paras. 1, 2, 5, 8, and 11); the Declaration and Programme of Action, World Conference on Human Rights, 14 to 25 June 1993 (I(15); I(19); I(27); I(30); II(B)(1), articles 19 to 24; II(B)2, articles 25 to 27); the Declaration on the Rights of Persons Belonging to National or Ethnic, Religious and Linguistic Minorities (articles 2, 3, 4(1), and 5); the World Conference against Racism, Racial Discrimination, Xenophobia and Related Forms of Intolerance, Declaration and Programme of Action (paragraphs 1, 2, 7, 9, 10, 16, 25, 38, 47, 48, 51, 66 and 104 of the Declaration); the Convention Relative to the Struggle against Discrimination in Education (articles 1, 3, and 4); the Declaration on Race and Racial Prejudice (Articles 1, 2, 3, 4, 5, 6, 7, 8, and 9); the Declaration on Human Rights of Individuals Who are not Nationals of the Country in which they Live (article 5(1)(b) and 5(1)(c); the Charter of Fundamental Rights of the European Union (articles 20 and 21); the European Convention for the Protection of Human Rights and Fundamental Freedoms (article 14); the European Social Charter (article 19(4), 19(5) and 19(7)); Protocol No. 12 to the European Convention for the Protection of Human Rights and Fundamental Freedoms (article 1); the African Charter on Human and Peoples' Rights, Banjul Charter (articles 2 and 3), the Arab Charter on Human Rights (article 2), and the Cairo Declaration of Human Rights in Islam (article 1). 62