Ahead of next Sunday's election for a 500-plus member assembly to rewrite the constitution and give the president more power, the opposition also plans a general strike - the second in weeks - on Wednesday and Thursday and a big protest march on Friday.
Even some of Maduro's opponents have cautioned that he could rally his supporters under a nationalist banner if the United States goes too far on sanctions as Venezuelans endure a brutal economic crisis with shortages of food and medicine.
A 48-hour general strike is now under way in Venezuela, in protest at the planned vote.
"Let them lock us all up".
Five people died during last week's strike as National Guard troops seeking to dismantle blockades fired teargas and rubber bullets at masked youths hurling stones and Molotov cocktails.
Photographs have emerged of Venezuelan military brass presenting soldiers with toilet paper in what appears to be socialist President Nicolas Maduro's way of rewarding them for their loyalty, opposition leader Henrique Capriles tweeted on July 23.
While populist governments may be novel in American politics, they are well known in Latin America where the steps populist leaders usually take not only to attain but specially to retain power are increasingly predictable.
Opposition leaders say Maduro is using the referendum as a means of imposing autocratic rule.
President Maduro has denounced this announcement by President Trump and has said that the Venezuelans will act like one united nation to fight the USA intervention.
Luis Almagro, secretary general of the Organization of American States, the Washington-based organization tasked with defending democracy in the hemisphere, said Tuesday he was designating a former prosecutor with the International Criminal Court to investigate the situation in Venezuela and help decide a course of action.
The National Assembly, controlled by the opposition, has already made moves toward what some are calling a "parallel" state by appointing 33 supreme court judges to rival ones loyal to Maduro.
The supreme court and Maduro's government have said those involved in the parallel court were committing "incitement to subversion".
"The elections are on Sunday and we really don't know what will happen", said one, Maria de los Angeles Pichardo, who left with her husband and son. "And all their property and accounts will be frozen". Finally, once they have succeeded in each one of these steps and the worldwide community reacts, populist governments become dictatorships.
If a Constituent Assembly is elected on July 30, there will be "a strong response", they insisted.
The opposition claimed Maduro was creating a dictatorship. The turnout represented 37% of the country's electorate, CNN calculated. When the opposition asked Venezuelans to express their opposition to the proposal in an informal July 16 plebiscite, more than seven million braved long lines and the threat of violence to do just that.
The oil export-dependent economy is shrinking 12 percent this year, after a contraction of 18 percent last year, according to the latest forecast from the International Monetary Fund. This is being followed by instigating the rightwing forces in Brazil to see that the popular former President Luiz Lulla da Silva is not allowed to stand for the Presidential elections in October 2018.