Donald Trump said last night he was considering possible military action against Venezuela in response to Nicolas Maduro's power grab.
Mr Trump told reporters at his New Jersey golf course that he was "not going to rule out" a military option".
"Venezuela is a mess. It is very dangerous mess and a very sad situation," Mr Trump said.
"The people are suffering and they are dying. We have many options for Venezuela including a possible military option if necessary," the US president said.
He added that it was "certainly something that we could pursue".
The Pentagon immediately responded, stating it had not received any orders on Venezuela.
A spokesman referred questions to the White House.
In a statement later, the White House said Mr Trump was ready to speak to Mr Maduro, but only when democracy had been restored.
"Since the start of this Administration, President Trump has asked that Maduro respect Venezuela's constitution, hold free and fair elections, release political prisoners, cease all human rights violations, and stop oppressing Venezuela's great people," the White House said.
"The Maduro regime has refused to heed this call, which has been echoed around the region and the world. Instead Maduro has chosen the path of dictatorship.
"The United States stands with the people of Venezuela in the face of their continued oppression by the Maduro regime. President Trump will gladly speak with the leader of Venezuela as soon as democracy is restored in that country."
Leon Panetta, the former US defence secretary, told CNN: "This is a president that comes out of the development industry in New York City, comes out of reality TV. I think he prides himself that talking is kind of his business....
"But when you're president of the United States, when you're commander-in-chief, this is not reality TV. This is a situation where he can't just talk down to everyone in the world and expect that somehow you can bully them to do what you think is right."
He added that this was "not a time for loose talk" but a time for "serious strategising" to find peaceful solutions.
More than 120 people have been killed and thousands arrested in four months of unrest in the South American country.
Mr Trump has been highly critical of Mr Maduro's moves to consolidate power, describing him as a "dictator".
The Trump administration has issued a series of sanctions against Mr Maduro and more than two dozen current and former Venezuelan officials.
But a military intervention would be an extraordinary escalation in response.
Mike Pence is heading to Latin America on Sunday amid deepening alarm over Venezuela's descent into political chaos.
The vice president's six-day, four-country tour will include stops in Cartagena, Colombia; Buenos Aires, Argentina; Santiago, Chile; and Panama City.
Meanwhile Peru expelled Venezuela's ambassador on Friday as regional pressure built on President Nicolas Maduro's government for allegedly trampling his country's constitutional order.
The Venezuelan government retaliated by ordering the head of Peru's embassy in Caracas to leave and called Peruvian President Pedro Pablo Kuczynski an "enemy" of Venezuela and of Latin American unity.
Peru gave Ambassador Diego Molero, a former Venezuelan defense minister, five days to leave the country.
As part of what it said was a firm commitment "to help restore Venezuela's democracy," Peru's administration also refused to accept a diplomatic protest made by Maduro over Peru's hosting this week of foreign ministers from 17 regional nations who refused to recognize the new, loyalist-packed special assembly that is to rewrite the constitution.
A few hours later, Venezuela's foreign ministry announced that it was giving Peru's top envoy in Caracas, Carlos Rossi, five days to leave the country. The statement also said Venezuela's ambassador in Lima had already returned to Caracas.
Peru's president has until recently been a lonely exception among Latin American leaders in openly condemning Maduro. Kuczynski, a former Wall Street investment banker who spent decades living in the U.S., is frequently mocked on Venezuelan state TV and was once referred to as the "empire's lapdog" by an official.
Responding to Mr Trump, Vladimir Padrino, Venezuela's defence minister, told state television, "It is an act of craziness. It is an act of supreme extremism. There is an extremist elite that rules the United States."
"As a soldier, I stand with the Venezuelan armed forces, and with the people. I am sure that we will all be on the front lines of defending the interests and sovereignty of this beloved Venezuela," he added.
Communications Minister Ernesto Villegas called Trump's remark "an unprecedented threat to national sovereignty."