The closed-door meetings with Japanese Prime Minister Shinzo Abe and Iranian President Hassan Rouhani came a day before Erdoğan's address to the UN General Assembly's 73rd session.
The theme of this year's general assembly is Making the United Nations Relevant to All People: Global Leadership and Shared Responsibilities for Peaceful, Equitable and Sustainable Societies.
Erdoğan also met UN Secretary-General Antonio Guterres on Monday at the organization's headquarters in the city.
Erdoğan's schedule in New York runs through Wednesday.
