evidence: Gibraltar is a colony. Since the 1960s, it has been on the United Nations list of "Non-Self-Governing Territories awaiting decolonisation". This colonial vestige is incompatible with resolution 1514 (XV) of 1960 on decolonisation. The United Nations has pointed out that, in the decolonisation process of Gibraltar, the applicable principle is not that of self-determination of peoples but rather that of restitution of Spanish territorial integrity. Spain has repeatedly asked the United Kingdom to enter into negotiations, in compliance with the provisions of the United Nations since 1965, to reach a definitive solution to this dispute. Gibraltar was ceded to the United Kingdom by the Treaty of Utrecht. However, only "the city and castle of Gibraltar together with its port, defences and fortresses belonging to it" were ceded. The isthmus, like the adjacent waters or the overlying airspace, was not ceded by Spain and has always remained under Spanish sovereignty. The continued de facto occupation by the British does not meet the requirements of international law for the acquisition of sovereignty. That is why Spain has always stressed that the occupation of the isthmus is illegal and contrary to international law and, therefore, has always demanded its unconditional return. Spain does not recognise the occupation of the isthmus or the fence as a border.