OSAKA, Japan — The annual Group of 20 summit meeting, which brings together President Trump and other world leaders, is intended to foster global economic cooperation. But with so many top officials in one place, it also serves as an all-purpose jamboree of nonstop formal and informal diplomatic activity.

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This year’s meeting takes place in Osaka, Japan, on Friday and Saturday, and the official agenda includes trade, artificial intelligence, women’s empowerment and climate change. If the members can reach consensus on those subjects and others, they will produce an official joint declaration at the end.

That might not be easy: President Emmanuel Macron of France, in a challenge to the United States, has threatened not to sign any joint statement that does not adequately address climate change. And Mr. Trump, before reaching Osaka, lashed out at Japan, Germany and India — all American allies.

Mr. Trump’s primary focus, however, is likely to be on a series of one-on-one meetings with foreign leaders. On Friday, he is to sit down with President Vladimir V. Putin of Russia, with whom he hopes to refresh relations, and on Saturday, he is to meet with President Xi Jinping of China, with whom he planned to discuss a trade standoff that has spooked global markets.