Maduro has remained determined to see through his plan, however, with backing from a loyal military.
Caracas: Small numbers of protesters on Friday defied a ban on demonstrations in Venezuela, ahead of a controversial weekend election called by President Nicolas Maduro that has already provoked deadly violence and international criticism.
Blockades went up across a few roads in Caracas and in a border town with Colombia, San Cristobal, but nothing on the massive scale seen earlier this week before the ban took effect.
"It's normal that there's fear, but people are still coming out into the streets despite it all," a lawmaker in the opposition-controlled National Assembly, Freddy Guevara, said at one of the Caracas protests.
Maduro on Thursday warned that those taking part in any new protests against his holding of the vote on Sunday to choose a "Constituent Assembly" to rewrite Venezuela's constitution risked up to 10 years in prison.
The threat appeared to dampen public anti-government demonstrations of the sort that, in the past four months, have led to 113 deaths eight of them during a two-day general strike that ended Thursday. But international censure of Maduro's stance remained fierce.
US Vice President Mike Pence spoke by telephone to a detained prominent Venezuelan opposition leader, Leopoldo Lopez, who early this month was moved from prison to house arrest.
In implicit support for the opposition, Pence praised Lopez's "courage." He also called for the "unconditional release of all political prisoners in Venezuela, free and fair elections, restoration of the National Assembly, and respect for human rights in Venezuela," a statement from his office said.
The United States this week imposed sanctions on 13 current and former Venezuelan officials, including police and army chiefs, over Maduro's plan.
Colombia's president, Juan Manuel Santos, also said his country would not recognize the results of Sunday's election in Venezuela, calling the basis of the Constituent Assembly "spurious."
Maduro has remained determined to see through his plan, however, with backing from a loyal military. "We have a card to play: a card that will win this game. And that card is the National Constituent Assembly," he said. He urged the opposition to stop its "insurrection" and hold talks instead. The leftist president has repeatedly accused the US of fomenting the unrest against him.
The new assembly would comprise 545 citizens chosen from across the country, and from societal sectors over which Maduro's government holds influence meaning opposition voices would be diluted or excluded.
The opposition, which calls the election of the body a ploy by an unpopular "dictator" to cling to power, has called for a boycott of the vote. Some 70 percent of Venezuelans oppose plans for the constituent assembly, and 80 percent reject Maduro's leadership, according to the polling firm Datanalisis.
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 credible election observers present.
Fears of open civil conflict have prompted thousands of Venezuelans to join an exodus into Colombia. The neighboring country said it would give 150,000 Venezuelans who had overstayed permission to visit another three months before they had to leave.
On Thursday, the United States ordered families of its embassy staff in Venezuela to leave. Washington and Ottawa also warned against their citizens making non-essential travel to the country.
The United Nations human rights office said it was "deeply concerned" about the "very tense and very difficult situation" in Venezuela. Some in Maduro's administration have broken ranks, most prominently his attorney general. Some diplomats resigned this week, including one at the UN and one at the embassy in Panama.