The precarious political situation in Venezuela intensified on Wednesday when US-backed opposition leader Juan Guaido declared himself interim president while President Nicolas Maduro cut diplomatic relations with the US, giving American diplomats 72 hours to leave the country.

US President Donald Trump said that the US had recognized Guaido, 35, head of the National Assembly, as interim president.

“Today, I am officially recognizing the President of the Venezuelan National Assembly, Juan Guaido, as the Interim President of Venezuela,” Trump said in a statement. “I will continue to use the full weight of United States economic and diplomatic power to press for the restoration of Venezuelan democracy.”

US Senator Marco Rubio of Florida tweeted on Wednesday: “Maduro has no authority to expel US diplomats or end diplomatic relations. The legitimate President @jguaido has asked US diplomats to stay in #Venezuela. Our diplomats leaving would be a tacit acceptance of Maduro legitimacy. Under no circumstances should we leave.”

At a rally Wednesday that brought hundreds of thousands into east Caracas, Guaido said Maduro had usurped power. Guaido promised to create a transitional government that would help the country escape its hyperinflationary economic collapse.

“I swear to assume all the powers of the presidency to secure an end to the usurpation,” Guaido said.

Joseph Palacios, a sociologist specializing in Latin American culture and a fellow at the University of Southern California, told China Daily that “the bilateral relationship was already damaged. I really think that it was a mistake for President Trump to do what he did in terms of acknowledging the opposition candidate as the interim president.”  

Palacio said the US should have waited to see how the street demonstrations unfolded.

He said he was not surprised to see Venezuela cut off the diplomatic relationship because “America did a hostile act” in acknowledging a president who was not elected.

Maduro, 56, was elected last year with 67.84 percent of the votes in a contest that critics said reflected a low turnout as a protest. He was sworn in as president on Jan 10 for another six-year term.

In a broadcast Wednesday from the presidential palace, Maduro accused the opposition of seeking to stage a coup with the support of the US, which he said was seeking to govern Venezuela from Washington.

“We’ve had enough interventionism, here we have dignity, damn it! Here is a people willing to defend this land,” said Maduro, flanked by top Socialist Party leaders, although the defense minister and members of the military high command were absent.

“The imperial government of the United States is leading a coup attempt against us in order to install a puppet presidency that they can control in Venezuela,” Maduro said.

So far, the military has stood by Maduro through two waves of street protests.

Other countries officially recognizing Guaido are Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Guatemala, Honduras, Panama, Paraguay and Peru.

Donald Tusk, European Council president, offered support to Guaido and called on other European nations to join him.

Mexico, which was once a vocal member of a regional bloc created to pressure Maduro to enact democratic reforms, under new leftist President Andres Manuel Lopez Obrador, said it would not take sides and called support for Guaido a violation of sovereignty.

The Trump administration could impose sanctions on Venezuelan oil as soon as this week, according to sources. Venezuela has the largest crude reserves in the world and is a major supplier to US refiners, though output is hovering near 70-year lows.

Venezuela’s hyperinflation is forecast to reach 10 million percent this year. Some 3 million Venezuelans have fled abroad over the past five years to escape shortages of food and medicine, according to the United Nations.

Reuters and Hong Xiao in New York contributed to this story.