Mr Maduro says the 545-member assembly, which will have the power to dissolve state institutions and rewrite the constitution, will bring peace to the convulsed country. They were not met with any immediate police presence.
In Caracas on Friday, Maduro opponents in several neighborhoods, from affluent Altamira to working-class Petare, used bricks and trash to erect dozens of barricades, which have become symbols of resistance.
An electoral expert, Eugenio Martinez, noted that most of Venezuela's 20 million voters would be able to vote twice, raising questions about the validity of final turnout and balloting figures, especially with no foreign election observers present. Prison terms of between five and 10 years could be imposed on those contravening the ban، Interior Minister Néstor Reverol said on Thursday. "We will fight", opposition leader and National Assembly Vice President Freddy Guevara told reporters Thursday, after the ban was announced. It is likely to follow the color revolution by force script the USA developed and implemented in several countries over the last decade.
"The goal is not only to write the constitution, the objective is to get rid of the National Assembly, which we won with two-thirds of the votes", Aria told RT.
It's not clear whether Venezuelans would have chosen to have the vote had Maduro asked them.
Opposition leaders have said they are willing to talk only if Sunday's vote is postponed.
"We urge the authorities to manage any protests against the Constituent Assembly in line with global human rights norms and standards", Elisabeth Throssell, spokeswoman for the Office of the UN High Commissioner for Human Rights, said in a statement Friday.
Juan Manuel Santos said he would not recognize this weekend's election to a constituent assembly in Venezuela.
Far from derail Maduro, the Venezuelan leader appeared emboldened by the sanctions, praising those accused by the US government of undermining the nation's democracy and abusing human rights.
Still, some worldwide companies are not ready to cease operations in the embattled South American country. He said the constituent assembly lacks legitimacy and therefore, his county can not accept the result.
Prominent opposition leader Leopoldo Lopez made a direct appeal to the military early Wednesday to withdraw its support from Maduro's plan, which he called a "constitutional fraud" aimed at eliminating democratic rule. Protests against Maduro have been going on since the end of March.
What is the new body?
The other 181 members will be drawn from unions - another source of Maduro support - civil and social groups, business groups, and indigenous communities.
"Constituent Assembly" would have the power rewrite the constitution and shut down the existing opposition-led legislature.
Maduro branded the United States punishment "illegal, insolent and unprecedented".
For months, violence has spiraled out of control as the struggle for food and medicine grows.
The country has been in unrest for four months with anger over high inflation, a severe shortage of basic food items and a deadly shortage of medical supplies.
"I believe that we should have a transitional government for at least two years that would attempt to decipher and dismantle the network of corruption that has been created", Arria said.
Streets in some parts of Caracas and nearby towns were near-empty during the strike as some Venezuelans stayed home from work.
That may have been more of an effort to pressure Mr Maduro than to respond to the country's security situation, which has been challenging for years, said one former senior Central Intelligence Agency official.
The street protests began in response to decisions by Venezuela's Supreme Court to temporarily assume some of the responsibilities of the opposition-minded National Assembly, and to revoke the immunity of the legislators.