NEW YORK (Reuters) - President Donald Trump will speak forcefully about the threat posed by North Korea during his first address to the United Nations on Tuesday while knocking those he sees as enabling Pyongyang.  He will speak in extremely tough terms about the North Korean menace and the threat it poses to our security and the security of all the nations in that room,  a White House official told reporters in a call previewing Trump s remarks at the U.N. General Assembly.  And he will talk about, as well, the enablement of the North Korean regime and what that means too,  the official said.  The official, who spoke on condition of anonymity, did not elaborate, but his mention of  enablement  was likely a reference to China, which has frustrated Trump by failing to rein in North Korean leader Kim Jong Un. North Korea s nuclear tests and missile launches have stirred global tensions Trump spoke to Chinese President Xi Jinping earlier on Monday and committed to keep up pressure on North Korea by enforcing U.N. resolutions, the White House said. On Tuesday, Trump is also expected to go hard against Iran during a speech that the official said would espouse the importance of state sovereignty.  It s an appeal to each nation to use sovereignty as the basis for mutual cooperation, the idea being that rather than appealing to a top-down model of global bureaucracy, it s a model that s from the nation-state up,  he said. Border control, trade and international agreements that are unfavorable to the United States represented threats to U.S. sovereignty, the official said. The theme is consistent with Trump s  America First  philosophy that helped him win election last year. [nL2N1LF26C] Trump has been critical of international organizations, including NATO and the United Nations. On Monday, he criticized the 193-nation body for a bloated bureaucracy and mismanagement, but said reforms would help it emerge stronger and more effective. 