What Trump will tell the United Nations

Trump before the beginning of the "Reforming the United Nations" meeting Monday at UN headquarters. Photo: Evan Vucci / AP

President Trump's speech Tuesday before the UN General Assembly will focus on North Korea's "destabilizing, hostile, and dangerous behavior," as well as the threat posed by Iran, a senior administration official told reporters on Monday.

Although the official would not go into details on what specific actions Trump will ask other nations to take with regard to the two countries, the official said Trump will stress that "nations cannot be bystanders to history." North Korea is a "shared menace" that will "only become more formidable" if nations don't do anything, the official said in a preview of the speech.