NEW YORK – President Donald Trump made an unexpected stop at a high-profile global climate summit at the United Nations on Monday, even though aides signaled for weeks that the president would not attend.

Trump took a seat in the auditorium at the United Nations as Prime Minister Narendra Modi of India began speaking at the event. Trump and Modi traveled together to Houston on Sunday and are expected to meet again later this week.

Just before he was scheduled to speak at a separate event on religious freedom, Trump sat next to Vice President Mike Pence and listened to Modi. He left after about 14 minutes and did not make remarks.

"The world needs to act now," Modi said, prompting applause from the president.

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Trump has faced widespread condemnation from other world leaders for starting the process of pulling the U.S. out of the Paris climate accord. The UN meeting on Monday is an attempt to hold the signatories of that deal to their commitments to reduce carbon emissions.

The summit culminates a week of international protests and marches aimed at drawing attention to the climate crisis. In New York City 1.1 million children were excused from classes to attend the Global Climate Strike rally. Organizers say around 250,000 people turned out in New York. Thousands filled the streets of San Francisco (40,000), Denver, (7,500), Boston (7,000), Chicago (3,000), Portland (2,000) and Washington, D.C., among other cities.

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Protests continued on Monday in Washington, D.C., where activists shut down major intersections and disrupted the morning commute.

Similar scenes took place worldwide in cities including Berlin (270,000), London (100,000) and across Australia (about 100,000 in Melbourne).

Greta Thunberg, the 16-year-old Swedish activist who sparked the international movement, delivered an emotional speech at the Climate Action Summit before Trump's surprise appearance.

"I shouldn't be up here. I should be back in school on the other side of the ocean, yet you come to us young people for hope. How dare you," she said.

"You have stolen my dreams and my childhood with your empty words."

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