His warning came in a televised speech after the government on Sunday unexpectedly won 18 of 23 states in a vote which the opposition calls fraudulent.
The order is Washington’s biggest sanctions blow to date against Maduro, meant to punish his government for what Trump has called an erosion of democracy.
President Nicolas Maduro sponsored last month’s election of the 545-member constituent assembly over objections from the opposition.
Following Trump’s statement that military intervention in Venezuela was an option, many Maduro critics are rejecting the idea of a foreign invasion.
Foreign ministers of Argentina, Paraguay, Uruguay and Brazil urged Maduro to release prisoners and immediately start a political transition.
The assembly is meant to be a legislative super-body designed to give Maduro powers to rewrite the constitution and sideline the opposition-led congress.
No oil-related measures were included in the announcement, but such measures remain under consideration, according to congressional sources.
Wuilly Arteaga had become an iconic face in anti-Maduro protests, playing the national anthem as tear gas enveloped him and rubber bullets flew around him.
Jesus Rojas and Zuleima Gonzalez were seized in central Anzoategui state after another appointee, Angel Zerpa, was arrested over the weekend.
The move raises the spectre of the development of a parallel state. The top court has warned that the naming of the alternate judges is illegal.
The majority-backed opposition want Venezuelans to close businesses, halt transport and barricade streets as part of a civil disobedience campaign.
Record high numbers turned out to participate in a historic dry run vote for the constituent assembly, aimed at easing tensions and creating a more representative constitution.
Luisa Ortega has said she is expecting to be fired after alleging human rights abuses and erosion of democracy under the country’s leftist president.
At least 79 people – including passers-by and security forces – have died in the daily exercises of democratic participation that began in April.
The death of Luis Alviarez, 18, brought the death toll in six weeks of protest to at least 39.
Dubbed the “Shit March”, thousands of opposition supporters again poured onto the streets decrying Venezuela’s economic crisis and demanding elections.
Maduro wants to create a new popular assembly with the power to re-write the constitution, which is being seen as a way to stifle anti-government protests.
The crisis-ridden Venezuela is one of the world’s most violent countries and it also has a notoriously overcrowded and violent jail system.
The wave of protests since early April against socialist President Nicolas Maduro have sparked Venezuela’s worst violence since 2014.
The announcement came after the OAS agreed on Wednesday to hold a meeting of foreign ministers to discuss the situation in Venezuela.
Twelve people have been killed in a renewed wave of demonstrations this month in incidents primarily involving security forces or armed civilians.
Opposition leaders have promised to keep up their protests, demanding the government call regional elections that have been delayed since last year, free almost 100 jailed opposition activists and respect the autonomy of the opposition-led Congress.
Once confined to specific corners of the world and largely ignored, the 21st century has seen a revival of populism in politics. But where is it headed?
A renewed wave of protests was sparked by a Supreme Court move to assume the powers of the opposition-led Congress and by barring Henrique Capriles from public office
The patently illegitimate regime of Nicolás Maduro is hanging on to power in Venezuela with the brute support of a complicit military.
The demonstrations were sparked by the Supreme Court’s attempt to take control of Venezuela’s opposition-led congress last week.
Protests also were staged in other cities and more are planned across the country for April 6.
Lenin Moreno secured 51.1% of the votes compared to Guillermo Lasso’s 48.9%, with just over 95% of votes counted, according to the electoral council, which is yet to declare a winner.
Polls show Moreno has pulled ahead of Lasso in the last weeks. He had 52.4% of valid votes versus Lasso’s 47.6% in a 18-21 March survey.
Brazil, Argentina, Mexico, Colombia, Chile, Guatemala and Panama expressed strong concerns while Peru withdrew its envoy terming it a rupture of democracy.
Last week, 14 nations urged elections and freedom of jailed opponents of President Maduro’s socialist government, turning up the pressure on him.
Triple digit inflation and a decaying socialist economic model have left medications ranging from simple anti-inflammatory drugs to chemotherapy medication out of reach for most Venezuelans.
The network had irked the socialist government with various reports, including one alleging passports and visas were being sold illegally at Venezuela’s embassy in Iraq.
Opponents of the unpopular Socialist leader say his administration should be focused on stocking empty supermarkets and pharmacies amid brutal shortages.
Naming a new Vice-President, Venezuela’s Nicolas Maduro announced a few changes in other key positions in his cabinet as well.
New governments were voted in, others struggled through crises, some economies recovered and one country inched closer to peace. Next year brings promise to some, stability to others and continued unrest elsewhere.
Roughly one person is lynched every three days in crisis-hit Venezuela as frustrated residents take revenge on suspected criminals.
President Maduro suspended the elimination of the country’s largest denomination bill, which had sparked cash shortages and nationwide unrest.
Venezuelan government officials failed to attend meetings, throwing cold water on Vatican-brokered attempts to bridge the country’s deep political crisis.
Enraged by last week’s suspension of their push for a referendum to remove Maduro, thousands turned out in protest against him.