Largest gathering of world leaders

The largest meeting of heads of state and government took place at the United Nations' 2005 World Summit at the UN Headquarters in New York, USA, on 14–16 September 2005, where 154 monarchs, presidents and prime ministers gathered to discuss a variety of major global issues, including poverty, climate change, nuclear proliferation and the protection of populations from genocide and war crimes.

While more leaders may have been present at state funerals, this is the largest organized meeting of senior government and state figures. According to UN estimates, 149 world leaders addressed the 2005 Summit, which comprised nearly 900 dignitaries at the level of minister or above plus 5,200 delegates and more than 2,200 journalists. The UN's meeting coverage and press team released the following details:

"Addressing the General Assembly on the final day of the 2005 World Summit were the Presidents of: Paraguay, Kyrgyzstan, Indonesia, Republic of Moldova, Panama, Poland, Togo, Bolivia, Croatia, Suriname, Portugal, Dominican Republic, Colombia, El Salvador, Guyana, Sierra Leone, Uganda, Federated States of Micronesia, Kiribati, Lebanon, Maldives, and Malawi.

"Also speaking to the Assembly were the Prime Ministers of: Lao People’s Democratic Republic, Greece, Australia, Norway, Grenada, Thailand, Liechtenstein, Saint Vincent and the Grenadines, Canada, Armenia, Tuvalu, Timor-Leste, Guinea-Bissau, Fiji, and Niger.

"Vice Presidents from Guatemala and Costa Rica, and Deputy Prime Ministers from Vanuatu, Turkmenistan, and Singapore also spoke. "The Foreign Ministers of Uzbekistan, Bahamas, Nicaragua, Chad, Azerbaijan, Nepal, Trinidad and Tobago, New Zealand, Egypt, Myanmar, Tunisia, Democratic Republic of the Congo, Tonga, Papua New Guinea, Sudan, Libya, Somalia, and Honduras also made statements.

"The King of Jordan, the Crown Prince of Bahrain, the Minister of Information and Culture and Personal Representative of the President of United Arab Emirates, the Minister of National Heritage and Culture and Special Envoy of the Sultan of Oman, the Secretary of State of the Holy See, the President of the National Assembly of Cuba, the Chairman of the National Transitional Government of Liberia, the Minister for Economic Affairs and Development of Mauritania, the Foreign Minister of the Palestinian Authority, and the representative of Yemen also addressed the Summit.

"Statements were also made by representatives of the League of Arab States, European Community, Organization of Islamic Conference, Inter-Parliamentary Union, Shanghai Cooperation Organization, International Union for Conservation of Nature and Natural Resources, Council of Europe, Commonwealth Secretariat, International Confederation of Free Trade Unions, Centre for Peruvian Women 'Flora Tristan', BHI Holdings Ltd., Asian Development Bank, and the African Development Bank."