• Trump threatens new tariffs on Russia over Ukraine war
• US president lectures world leaders on migration, climate change
• Calls climate change a con job

UNITED NATIONS, Sept 23 (Reuters) - U.S. President Donald Trump argued for lower levels of global migration and urged a turn away from climate change policies on Tuesday in a combative, wide-ranging speech to the U.N. General Assembly that leveled scathing criticism of world leaders.

The 56-minute speech was a rebuke to the world body and a return to form for Trump, who routinely bashed the U.N. during his first term as president. Leaders gave him polite applause when he exited the chamber.