Donald Trump says “all options are on the table” as the US seeks to push Venezuelan President Nicolas Maduro to give up power.
But Mr Maduro – backed by the country’s military – went on the offensive against an opposition leader who declared himself interim president and his US supporters.
The battle between Mr Maduro and Juan Guaido sets up a potentially explosive struggle for power in the crisis-plagued South American nation.
Washington has refused to comply, but ordered its non-essential staff to leave the country, citing security concerns.
The Trump administration says Mr Maduro’s order is not legal because the US no longer recognises him as Venezuela’s legitimate leader.
“They believe they have a colonial hold in Venezuela, where they decide what they want to do,” Mr Maduro said in an address broadcast live on state TV.
“You must fulfil my order from the government of Venezuela.”
Meanwhile, all eyes were on Mr Guaido whose whereabouts have been a mystery since the 35-year-old was symbolically sworn in on Wednesday before tens of thousands of cheering supporters, promising to uphold the constitution and rid Venezuela of Mr Maduro’s rule.
Speaking from an undisclosed location, he told Univision he would consider granting amnesty to Mr Maduro and his allies if they helped return Venezuela to democracy.
“Amnesty is on the table,” said Mr Guaido, who weeks earlier was named head of the opposition-controlled congress.
“Those guarantees are for all those who are willing to side with the constitution to recover the constitutional order.”
Much of the international community rallied behind Mr Guaido, with Canada and numerous Latin American and European countries announcing that they recognised his claim to the presidency.
Mr Trump promised to use the “full weight” of US economic and diplomatic power to push for the restoration of Venezuela’s democracy.
Mr Maduro has been increasingly accused of undemocratic behaviour by his opponents, and has presided over skyrocketing inflation, a collapsing economy and widespread shortages of basic goods.
Russia, China, Iran, Syria, Cuba and Turkey have voiced their backing for Mr Maduro’s government.