- 80 State Date of signature Date of receipt of the instrument of ratification or accession Ukraine United Kingdom of Great Britain and Northern Ireland United States of America Uruguay Uzbekistan 27 February 1986 15 March 1985 24 February 1987 8 December 1988 18 April 1988 4 February 1985 21 October 1994 24 October 1986 28 September 1995a Venezuela Yemen Yugoslavia Zambia 15 February 1985 29 July 1991 5 November 1991a 10 September 1991b 7 October 1998a a Accession. b Succession. 18 April 1989