Surrounded by top-ranking United Socialist Party (PSUV) officials, President Maduro said that the assembly was needed to instil peace against a violent opposition.
An influential group of U.S. senators filed sweeping legislation on Wednesday to address the crisis in Venezuela, including sanctioning individuals responsible for undermining democracy or involved in corruption.
Rafaela Requesens, student leader of the Federation of University Centres of the UCV (FCU-UCV), said that the President's proposal to amend the Constitution by convening the National Constituent Assembly "does not make sense" because "what has to change" is the government of Maduro.
Having failed to trigger a referendum on his rule a year ago, the opposition is calling for delayed state gubernatorial elections to be held as soon as possible, and for the next presidential election slated for 2018 to be brought forward.
He posted his strongly-worded message after an 18-year-old musician was killed at a rally in Caracas. That attempt was quickly walked back - but not before it catalyzed an opposition that had already been simmering over rampant food shortages and indefinitely postponed elections. The proposed assembly is a repeat of a move made by Maduro's predecessor, Hugo Chávez, in 1999. His opponents claim the rest of the seats would probably be filled with pre-selected government supporters.
The opposition and government have accused each other of fomenting violence.
In his statement, Dudamel urged political leaders to stop the violence, but also directed much of his criticism at Maduro's decision this week to convoke a constituent assembly to rewrite the country's constitution.
Refering to the large flow of oil from Venezuela to India, the ambassador said President Maduro was totally supportive of it, with oil reserves being under government control.
Opposition parties and students have denounced what they called heavy-handed police tactics.
"If there is a constitution that is the result of a minority imposing rules, the government will fall". They protected themselves with homemade shields, painted in bright colours and decorated with slogans like "Liberty!" and "Murderer Maduro!"
The letter did not list specific actions, but said the behavior of the government only "weakened the Bolivarian process" set in motion by Chávez and "effectively works in favor of the enemies' plans".
The death of the 38 year-old officer in the central state of Carabobo means three dozen people have now died in the month of protests. "He is sending the most radical people" to deal with protests, Capriles said.
Prosecutors in the country say at least 35 people have been killed in over a month of unrest.
This story features material from Morning Star and worldwide wire services.