On minimum core obligations, the Committee on Economic, Social and Cultural Rights states:
"On the basis of the extensive experience gained by the Committee, as well as by the body that preceded it, over a period of more than a decade of examining States parties’ reports the Committee is of the view that a minimum core obligation to ensure the satisfaction of, at the very least, minimum essential levels of each of the rights is incumbent upon every State party. Thus, for example, a State party in which any significant number of individuals is deprived of (...) the most basic forms of education is, prima facie, failing to discharge its obligations under the Covenant. If the Covenant were to be read in such a way as not to establish such a minimum core obligation, it would be largely deprived of its raison d’être. By the same token, it must be noted that any assessment as to whether a State has discharged its minimum core obligation must also take account of resource constraints applying within the country concerned. Article 2 (1) obligates each State party to take the necessary steps “to the maximum of its available resources”. In order for a State party to be able to attribute its failure to meet at least its minimum core obligations to a lack of available resources it must demonstrate that every effort has been made to use all resources that are at its disposition in an effort to satisfy, as a matter of priority, those minimum obligations."
Committee on Economic, Social and Cultural Rights (1990) General Comment 3: The Nature of States Parties' Obligations (Art. 2, Para. 1, of the Covenant): Para.10.