Iranian President Mahmoud Ahmadinejab met with United Nations Secretary-General Ban Ki-moon on Sunday in New York.
Ban Ki-moon will attend a week's worth of United Nations events, including a Millennium Development Goals summit and the General Assembly's General Debate.
Ahmadinejad is scheduled to speak at both events and will also hold a separate press conference during his visit.
His presence in New York has led to a number of planned protests, both by groups that criticize the human rights situation in Iran as well as the country's nuclear program.
Permanent members of the UN Security Council, along with Germany, are expected to discuss Iran and its nuclear program on Wednesday.
Last week, Western powers accused Iran of trying to intimidate the UN atomic agency by barring some nuclear inspectors. The United States warned the Islamic state of possible diplomatic consequences.