UNITED NATIONS — The American envoy to the United Nations, Nikki R. Haley, described the United States on Wednesday as the “moral conscience” of the world, and she dismissed the United Nations Human Rights Council as “so corrupt” without offering evidence.

Ms. Haley said the United States would never close its doors to foreigners who flee persecution, even as she defended the Trump administration’s travel ban, which closed the door to refugees from six war-torn, mainly Muslim nations.

She insisted that American taxpayers should get value for the money they contribute to the United Nations. She said nothing about whether the United States would help head off a potential humanitarian disaster from famine that the United Nations has warned is looming over 20 million people abroad.

Ms. Haley’s remarks, made at the Council on Foreign Relations in New York early Wednesday morning, were her first as ambassador to an audience of foreign policy experts. She called it “an intimidating crowd.”