# List of parties to the Environmental Modification Convention

The list of parties to the Environmental Modification Convention encompasses the states who have signed and ratified or acceded to the international agreement prohibiting military use of environmental modification techniques.
On May 18, 1977, the Environmental Modification Convention (ENMOD) was opened for signature. North Yemen became the first state to deposit the treaty on 20 July 1977. The treaty came into force and closed for signature on October 5, 1978. Since then, states that did not sign the treaty can now only accede to it. The instrument of ratification, accession, or succession is deposited with the Secretary-General of the United Nations
As of 2022, 78 states have ratified or acceded to the treaty, most recently the State of Palestine on 29 December 2017. A further 16 states have signed but not ratified the treaty.
As of March 2013 the third review conference had not been scheduled as there were under 10 respondents showing interest in reconvening.

## List of parties

| State | Signed | Ratified or Acceded | Method |
| Afghanistan | | Oct 22, 1985 | Accession |
| Algeria | | Dec 19, 1991 | Accession |
| Antigua and Barbuda | | Oct 25, 1988 | Succession from United Kingdom |
| Argentina | | Mar 20, 1987 | Accession |
| Armenia | | May 15, 2002 | Accession |
| Australia | May 31, 1978 | Sep 7, 1984 | Ratification |
| Austria | | Jan 17, 1990 | Accession |
| Bangladesh | | Oct 3, 1979 | Accession |
| Belarus | May 18, 1977 | Jun 7, 1978 | Ratification as Byelorussian SSR |
| Belgium | May 18, 1977 | Jul 12, 1982 | Ratification |
| Benin | Jun 10, 1977 | Jun 30, 1986 | Ratification |
| Brazil | Nov 9, 1977 | Oct 12, 1984 | Ratification |
| Bulgaria | May 18, 1977 | May 31, 1978 | Ratification |
| Cameroon | | Apr 18, 2011 | Accession |
| Canada | May 18, 1977 | Jun 11, 1981 | Ratification |
| Cape Verde | | Oct 3, 1979 | Accession |
| Chile | | Apr 26, 1994 | Accession |
| China | | Jun 8, 2005 | Accession |
| Costa Rica | | Feb 7, 1996 | Accession |
| Cuba | Sep 23, 1977 | Apr 10, 1978 | Ratification |
| Cyprus | Oct 7, 1977 | Apr 12, 1978 | Ratification |
| Czech Republic | | Feb 22, 1993 | Succession from Czechoslovakia Signed 18 May 1977 Ratified 12 May 1978 |
| Denmark | May 18, 1977 | Apr 19, 1978 | Ratification |
| Dominica | | Nov 9, 1992 | Succession from United Kingdom |
| Egypt | | Apr 1, 1982 | Accession |
| Estonia | | Apr 14, 2011 | Accession |
| Finland | May 18, 1977 | May 12, 1978 | Ratification |
| Germany | May 18, 1977 | May 24, 1983 | Ratification as West Germany Also East Germany Signed 18 May 1977 Ratified 25 May 1978 |
| Ghana | Mar 21, 1978 | Jun 22, 1978 | Ratification |
| Greece | | Aug 23, 1983 | Accession |
| Guatemala | | Mar 21, 1988 | Accession |
| Honduras | | Aug 16, 2010 | Accession |
| Hungary | May 18, 1977 | Apr 19, 1978 | Ratification |
| India | Dec 15, 1977 | Dec 15, 1978 | Ratification |
| Ireland | May 18, 1977 | Dec 16, 1982 | Ratification |
| Italy | May 18, 1977 | Nov 27, 1981 | Ratification |
| Japan | | Jun 9, 1982 | Accession |
| Kazakhstan | | Apr 25, 2005 | Accession |
| Kuwait | | Jan 2, 1980 | Accession |
| Kyrgyzstan | | Jun 15, 2015 | Accession |
| Laos | Apr 13, 1978 | Oct 5, 1978 | Ratification |
| Lithuania | | Apr 16, 2002 | Accession |
| Malawi | | Oct 5, 1978 | Accession |
| Mauritius | | Dec 9, 1992 | Accession |
| Mongolia | May 18, 1977 | May 19, 1978 | Ratification |
| Netherlands | May 18, 1977 | Apr 15, 1983 | Ratification |
| New Zealand | | Sep 7, 1984 | Accession, includes Cook Islands and Niue |
| Nicaragua | Aug 11, 1977 | Sep 6, 2007 | Ratification |
| Niger | | Feb 17, 1993 | Accession |
| North Korea | | Nov 8, 1984 | Accession |
| Norway | May 18, 1977 | Feb 15, 1979 | Ratification |
| Pakistan | | Feb 27, 1986 | Accession |
| Palestine | | Dec 29, 2017 | Accession |
| Panama | | May 13, 2003 | Accession |
| Papua New Guinea | | Oct 28, 1980 | Accession |
| Poland | May 18, 1977 | Jun 8, 1978 | Ratification |
| Romania | May 18, 1977 | May 6, 1983 | Ratification |
| Russia | May 18, 1977 | May 30, 1978 | Ratification as Soviet Union |
| Saint Lucia | | May 27, 1993 | Succession from United Kingdom |
| Saint Vincent and the Grenadines | | Apr 27, 1999 | Succession from United Kingdom |
| Sao Tome and Principe | | Oct 5, 1979 | Accession |
| Slovakia | | May 28, 1993 | Succession from Czechoslovakia Signed 18 May 1977 Ratified 12 May 1978 |
| Slovenia | | Apr 20, 2005 | Accession |
| Solomon Islands | | Jun 19, 1981 | Succession from United Kingdom |
| South Korea | | Dec 2, 1986 | Accession |
| Spain | May 18, 1977 | Jul 19, 1978 | Ratification |
| Sri Lanka | Jun 8, 1977 | Apr 25, 1978 | Ratification |
| Sweden | | Apr 27, 1984 | Accession |
| Switzerland | | Aug 5, 1988 | Accession |
| Tajikistan | | Oct 12, 1999 | Accession |
| Tunisia | May 11, 1978 | May 11, 1978 | Ratification |
| Ukraine | May 18, 1977 | Jun 13, 1978 | Ratification as Ukrainian SSR |
| United Kingdom | May 18, 1977 | May 16, 1978 | Ratification |
| United States | May 18, 1977 | Jan 17, 1980 | Ratification |
| Uruguay | | Sep 16, 1993 | Accession |
| Uzbekistan | | May 26, 1993 | Accession |
| Vietnam | | Aug 26, 1980 | Accession |
| Yemen | May 18, 1977 | Jul 20, 1977 | Ratification as North Yemen South Yemen also acceded 12 June 1979 prior to Yemeni unification. |

## States that have signed but not ratified

| State | Signed |
| Bolivia | May 18, 1977 |
| Democratic Republic of the Congo Signed as Zaire | Feb 28, 1978 |
| Ethiopia | May 18, 1977 |
| Holy See | May 27, 1977 |
| Iceland | May 18, 1977 |
| Iran | May 18, 1977 |
| Iraq | Aug 15, 1977 |
| Lebanon | May 18, 1977 |
| Liberia | May 18, 1977 |
| Luxembourg | May 18, 1977 |
| Morocco | May 18, 1977 |
| Portugal | May 18, 1977 |
| Sierra Leone | Apr 12, 1978 |
| Syria | Aug 4, 1977 |
| Turkey | May 18, 1977 |
| Uganda | May 18, 1977 |

## States that have not signed

101 UN member states have never signed the treaty.
* Albania
* Andorra
* Angola
* Azerbaijan
* Bahamas
* Bahrain
* Barbados
* Belize
* Bhutan
* Bosnia and Herzegovina
* Botswana
* Brunei
* Burkina Faso
* Burundi
* Cambodia
* Central African Republic
* Chad
* Colombia
* Comoros
* Republic of the Congo
* Croatia
* Djibouti
* Dominican Republic
* Ecuador
* El Salvador
* Equatorial Guinea
* Eritrea
* Fiji
* France
* Gabon
* Gambia
* Georgia
* Grenada
* Guinea
* Guinea-Bissau
* Guyana
* Haiti
* Indonesia
* Israel
* Ivory Coast
* Jamaica
* Jordan
* Kenya
* Kiribati
* Latvia
* Lesotho
* Libya
* Liechtenstein
* North Macedonia
* Madagascar
* Malaysia
* Maldives
* Mali
* Malta
* Marshall Islands
* Mauritania
* Mexico
* Micronesia
* Moldova
* Monaco
* Montenegro
* Mozambique
* Myanmar
* Namibia
* Nauru
* Nepal
* Nigeria
* Oman
* Palau
* Paraguay
* Peru
* Philippines
* Qatar
* Rwanda
* Saint Kitts and Nevis
* Samoa
* San Marino
* Saudi Arabia
* Senegal
* Serbia
* Seychelles
* Singapore
* Somalia
* South Africa
* South Sudan
* Sudan
* Suriname
* Swaziland
* Tanzania
* Thailand
* Timor Leste
* Togo
* Tonga
* Trinidad and Tobago
* Turkmenistan
* Tuvalu
* United Arab Emirates
* Vanuatu
* Venezuela
* Zambia
* Zimbabwe
The Cook Islands and Niue, two associated states of New Zealand which have had their "full treaty-making capacity" recognised by United Nations Secretariat, are not parties to the treaty but are bound by its provisions by virtue of their administration by New Zealand when the latter ratified the ENMOD convention.