State Nigeria Norway a/ Date of signature Date of receipt of the instrument of ratification or accession 28 July 1988 4 February 1985 9 July 1986 Panama 22 February 1985 24 August 1987 Paraguay 23 October 1989 12 March 1990 Peru 29 May 1985 Philippines Poland a/ Portugal a/ 18 June 1986 b/ 13 January 1986 4 February 1985 Republic of Korea Senegal 9 February 1989 18 December 1990 b/ 10 December 1985 3 March 1987 4 February 1985 21 August 1986 Seychelles Sierra Leone 26 July 1989 9 January 1995 b/ Romania Russian Federation a/ 7 July 1988 5 May 1992 b/ 18 March 1985 Slovakia 29 May 1993 b/ Slovenia a/ 16 July 1993 b/ Somalia 24 January 1990 b/ South Africa Spain a/ 29 January 1993 4 February 1985 Sri Lanka 21 October 1987 3 January 1994 b/ Sudan 4 June 1986 Sweden a/ 4 February 1985 8 January 1986 Switzerland a/ 4 February 1985 2 December 1986 Tajikistan 11 January 1995 b/ The Former Yugoslav Republic of Macedonia 12 December 1994 c/ Togo a/ 25 March 1987 18 November 1987 Tunisia a/ 26 August 1987 23 September 1988 Turkey a/ 25 January 1988 Uganda 3 November 1986 b/ Ukraine 27 February 1986 United Kingdom of Great Britain and Northern Ireland d/ 15 March 1985 United States of America d/ 18 April 1988 Uruguay a/ Venezuela a/ 2 August 1988 4 February 1985 15 February 1985 -34- 24 February 1987 8 December 1988 21 October 1994 24 October 1986 29 July 1991