US president Barack Obama and his Russian and Chinese counterparts Vladimir Putin and Xi Jinping are three of more than 150 heads of state from all over the world due to take the stage at the UN general assembly in New York.

Significantly, the leaders of the three global superpowers are to address the 70th session of the UN's annual debate in rapid succession on the first day of the diplomatic shindig, which is to be opened this morning at 9am local time by UN secretary general Ban Ki-moon, whose annual report is to be followed by a keynote speech from the assembly president, Mogens Lykketoft of Denmark.

As per tradition, the head of state of Brazil, Dilma Rousseff, will be the first national leader to speak. She will be followed by 36 other heads of state, range between monarchs, presidents and prime ministers. Among them are Iranian president Hassan Rouhani, France's François Hollande, Cuba's Raúl Castro, Egypt's Abdel Fattah Al Sisi, Zimbabwean dictator Robert Mugabe and Argentina's Cristina Fernández de Kirchner.

The civil war in Syria and the related refugee crisis in Europe, the Iranian nuclear deal and the tensions in Ukraine are expected to be hot topics. Many leaders have already taken part in a run-up three-day UN event on sustainable development. The General Assembly concludes its works on 3 October.

You can watch all the addresses live here:

UN 70th General Assembly first day speakers

1. Secretary-General of the United Nations - H.E. Mr. Ban Ki-moon
Secretary-General

2. President of the General Assembly (opening) - H.E. Mr. Mogens Lykketoft
President of the 70th session of the General Assembly

3. Brazil - H.E. Mrs. Dilma Rousseff
President

4. United States of America - H.E. Mr. Barack Obama
President

5. Poland - H.E. Mr. Andrzej Duda
President

6. China - H.E. Mr. Xi Jinping
President

7. Jordan H.M. Mr. Abdullah II Ibn Al Hussein
King

8. Russian Federation - H.E. Mr. Vladimir Putin
President

9. Republic of Korea - H.E. Mr. Park Geun-hye
President

10. Iran (Islamic Republic of) - H.E. Mr. Hassan Rouhani
President

11. France - H.E. Mr. François Hollande
President

12. Qatar - H.H. Sheikh Tamim Bin Hamad Al-Thani
Emir

13. Mozambique - H.E. Mr. Filipe Jacinto Nyusi
President

14. Netherlands - H.M. Mr. Willem-Alexander
King

15. Kazakhstan - H.E. Mr. Nursultan Nazarbayev
President

16. Mexico - H.E. Mr. Enrique Peña Nieto
President

17. Portugal - H.E. Mr. Aníbal António Cavaco Silva
President

18. Denmark - H.E. Mr. Lars Løkke Rasmussen
Prime Minister

19. Ethiopia - H.E. Mr. Hailemariam Desalegn
Prime Minister

20. Uganda - H.E. Mr. Yoweri Kaguta Museveni
President

21. Chile - H.E. Mrs. Michelle Bachelet Jeria
President

22. Cuba - H.E. Mr. Raúl Castro Ruz
President

23. South Africa - H.E. Mr. Jacob Zuma
President

24. Egypt - H.E. Mr. Abdel Fattah al-Sisi
President

25. Switzerland - H.E. Mrs. Simonetta Sommaruga
President

26. Zimbabwe - H.E. Mr. Robert Mugabe
President

27. Argentina - H.E. Mrs. Cristina Fernández de Kirchner
President

28. Belarus - H.E. Mr. Alexander Lukashenko
President

29. Nigeria - H.E. Mr. Muhammadu Buhari
President

30. Gabon - H.E. Mr. Ali Bongo Ondimba
President

31. Paraguay - H.E. Mr. Horacio Manuel Cartes Jara
President

32. Kenya - H.E. Mr. Uhuru Kenyatta
President

33. Turkmenistan - H.E. Mr. Gurbanguly Berdimuhamedov
President

34. Senegal - H.E. Mr. Macky Sall
President

35. Mali - H.E. Mr. Ibrahim Boubacar Keita
President

36. Ecuador - H.E. Mr. Rafael Correa Delgado
President

37. Bolivia (Plurinational State of) - H.E. Mr. Evo Morales Ayma
President

38. Kiribati - H.E. Mr. Anote Tong
Head of Government

39. Peru - H.E. Mr. Ollanta Humala Tasso
President