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Good morning.

Here’s what you need to know:

• Trump’s warning to North Korea.

If the U.S. is forced to defend itself or its allies, “we will have no choice but to totally destroy North Korea,” President Trump told the U.N General Assembly this morning. Catch up with our live coverage.

Secretary General António Guterres spoke about climate change, Myanmar and trust among nations. Also looming over the assembly this year are issues like the debate over climate change.