Brazil's president Jair Bolsonaro arrives ahead of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

U.S. Vice President Mike Pence arrives ahead of the start of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

A security personnel is seen at U.N. headquarters during the United Nations General Assembly in New York City, New York, U.S., September 23, 2019.

A general view of United Nations headquarters on midtown Manhattan's East Side ahead of the 74th UN General Assembly in New York City, New York, U.S., September 23, 2019.

A member of the delegation from Peru waits in the General Assembly Hall ahead of the start of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

U.S. President Donald Trump talks to German Chancellor Angela Merkel at the U.N. headquarters in New York City, New York, U.S., September 24, 2019. Guido Bergmann/Bundesregierung/Handout via REUTERS.

Organization for Economic Cooperation and Development (OECD) Secretary-General Angel Gurria speaks with India's Prime Minister Narendra Modi at a luncheon during the 74th session of the United Nations General Assembly (UNGA) at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

Men walk near a security checkpoint near U.N. headquarters during the 2019 United Nations Climate Action Summit in New York City, New York, U.S., September 23, 2019.

U.S. President Donald Trump signs a memorandum of defense with Singapore's Prime Minister Lee Hsien Loong prior to their bilateral meeting on the sidelines of the annual United Nations General Assembly in New York City, New York, U.S., September 23, 2019.

Delegates walk on the grounds of the United Nations during the 2019 United Nations Climate Action Summit at U.N. headquarters in New York City, New York, U.S., September 23, 2019.

Britain's Prime Minister Boris Johnson speaks during an Emergency Declaration for Nature and People event after the 2019 United Nations Climate Action Summit at the U.N. headquarters in New York City, New York, U.S., September 23, 2019.

Bolivia's President Evo Morales arrives ahead of the start of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

President of the General Assembly Tijjani Muhammad-Bande of Nigeria gavels the opening of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

U.S. Vice President Mike Pence and U.S. Secretary of State Mike Pompeo arrive for the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

Turkey's President Recep Tayyip Erdogan arrives to attend the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

U.S. President Donald Trump addresses the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

White House senior advisor Ivanka Trump arrives for the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

U.S. President Donald Trump holds a bilateral meeting with British Prime Minister Boris Johnson on the sidelines of the annual United Nations General Assembly in New York City, New York, U.S., September 24, 2019.

Palestinian President Mahmoud Abbas arrives ahead of the start of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

A member of the Venezuelan delegation holds a book during the speech of U.S. President Donald Trump during the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

16-year-old Swedish Climate activist Greta Thunberg speaks at the 2019 United Nations Climate Action Summit at U.N. headquarters in New York City, New York, U.S., September 23, 2019.

U.S. President Donald Trump holds a bilateral meeting with South Korea's President Moon Jae-in on the sidelines of the annual United Nations General Assembly in New York City, New York, U.S., September 23, 2019.

Turkey's President Recep Tayyip Erdogan holds up a map as he addresses the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

U.S. President Donald Trump meets with Egypt's President Abdel Fattah el-Sisi on the sidelines of the annual United Nations General Assembly in New York City, New York, U.S., September 23, 2019.

Swedish environmental activist Greta Thunberg watches as U.S. President Donald Trump enters the United Nations to speak with reporters in a still image from video taken in New York City, U.S. September 23, 2019.

Men in matching clothing speak to each other in the cafeteria at United Nations headquarters during the 2019 United Nations Climate Action Summit in New York City, New York, U.S., September 23, 2019.

Former United Nations Secretary General Ban Ki-moon arrives ahead of the start of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

New Zealand's Prime Minister Jacinda Ardern (R) and Sheryl Sandberg, COO of Facebook and current chair of the Global Internet Forum to Counter Terrorism (GIFCT), arrive to give a news conference on the sidelines during the 2019 United Nations Climate Action Summit at U.N. headquarters in New York City, New York, U.S., September 23, 2019.

French President Emmanuel Macron shakes hands with Iranian President Hassan Rouhani during their meeting on the sidelines of the United Nations General Assembly in New York, U.S., September 23, 2019.

Croatia's President Kolinda Grabar-Kitarovic arrives ahead of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

Ukraine's President Volodymyr Zelensky sits with his delegation at the start of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

German Chancellor Angela Merkel arrives ahead of the start of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

United Nations Secretary General Antonio Guterres addresses the opening of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

Pakistan's Prime Minister Imran Khan arrives ahead of the start of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

Croatia's President Kolinda Grabar-Kitarovic holds up a photograph as she addresses the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

United Nations Secretary General Antonio Guterres addresses the opening of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

A translator translates U.S. President Donald Trump's words into Arabic as President Trump addresses the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

Former New York City Mayor Rudy Giuliani speaks during a rally to support a leadership change in Iran outside the U.N. headquarters in New York City, New York, U.S., September 24, 2019.

South Korea's President Moon Jae-in bows at the podium while he addresses the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

Ukraine's President Volodymyr Zelenskiy attends a luncheon for world leaders at the 74th session of the United Nations General Assembly (UNGA) at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

U.S. President Donald Trump shares a toast at a luncheon for world leaders at the 74th session of the United Nations General Assembly (UNGA) at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

French President Emmanuel Macron finishes his address to the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

German Chancellor Angela Merkel talks to 16-year-old Swedish climate activist Greta Thunberg during the 2019 United Nations Climate Action Summit at U.N. headquarters in New York City, New York, U.S., September 23, 2019. Steffen Seibert/Bundesregierung/Handout via REUTERS.

Video segments play during the opening ceremony of the 2019 United Nations Climate Action Summit at U.N. headquarters in New York City, New York, U.S., September 23, 2019.

U.S. Secretary of State Mike Pompeo attends as U.S. President Donald Trump meets with South Korea’s President Moon Jae-in in New York, U.S. September 23, 2019.

U.S. President Donald Trump speaks while meeting with South Korea's President Moon Jae-in on the sidelines of the annual United Nations General Assembly in New York City, New York, U.S., September 23, 2019.

Queen Maxima of the Netherlands arrives ahead of the start of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.

U.S. President Donald Trump checks his watch as he attends the 2019 United Nations Climate Action Summit at U.N. headquarters in New York City, New York, U.S., September 23, 2019.

Egypt's President Abdel Fattah Al Sisi arrives ahead of the start of the 74th session of the United Nations General Assembly at U.N. headquarters in New York City, New York, U.S., September 24, 2019.