Antigua and Barbuda joined the UN on 11 November 1981. It belongs to ACP, C, Caricom, CDB, ECLAC, FAO, G-77, IBRD, ICAO, ICFTU, ICRM, IFAD, IFC, IFRCS, ILO, IMF, IMO, Interpol, IOC, ISO (subscriber), ITU, NAM (observer), OAS, OECS, OPANAL, UN, UNCTAD, UNESCO, UPU, WCL, WFTU, WHO, WIPO, WMO, WTRO. Two areas totaling about 365 hectares (900 acres) are leased to the United States for use as tracking stations for space vehicles and missiles. In May 1987, the prime ministers of Antigua and Barbuda and the six other OECS member-states voted to create a single nation; national referendums on the issue were to be held. The referendums were later defeated and the seven nations remained separate.