Transcript for Venezuelans swarm the streets to call for president's resignation

And now, the warning tonight for U.S. Diplomats in swen sway la. They have 72 hours to get out of the country. President trump no longer recognizing that country's leader as the president. Instead, recognizing an opposition leader as the interim president, as thousands take to the streets in Venezuela. As you know, we have reported for years from Venezuela, on an company in freefall, little food, medicine and skyrocketing prices. ABC's Matt Gutman is back on this tonight. Reporter: Tonight, the emergency unfolding in Venezuela. Tens of thousands braving tear gas swarming the streets for hours today, calling for Venezuela's president Nicolas maduro to step down. And tonight, president trump speaking out, no longer recognizing maduro as Venezuela's president. We're not considering anything, but all options are on the table. Reporter: The U.S. And other countries are now recognizing this 35-year-old as the country's interim president. Juan guaido is the head of the opposition, and today, he was sworn in as president by the national assembly, which calls maduro illegitimate. Maduro firing back tonight, calling this an american-led coup, giving American diplomats 72 hours to get out. For three years now, we've been reporting on Venezuela's collapsing economy. Millions once middle class fleeing Venezuela, looking for food and medicine. It's hard to imagine when this boy came here, he was about nine pounds and now he's -- he's about 13 pounds. That report just a couple of weeks back. Matt, 72 hours to get out now for American diplomats. And you've lined they're taking this very seriously? Reporter: Very seriously, David. It is extraordinarily rare for an entire diplomatic mission to be expelled. I'm told that officials and their dependents have go bags packed already and it is very possible that we could see a has exodus of Americans from Venezuela in the coming days. David? Matt Gutman on this for us again tonight.

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