"It constitutes a rupture of the constitutional order," the attorney general said, raising a pocket-size copy of the Venezuelan Constitution in her left hand and standing in front of the Venezuelan flag.
Ortega made the statement during her annual State of the Attorney General's Office address in Caracas. The statement is significant because it breaks with the government's official position.
Venezuelan's opposition has long perceived the attorney general as being loyal to the socialist government of President Nicolás Maduro
"It is my obligation to express in front of the country my deep concern about this event (the ruling)" Ortega added.
In a surprising move late Wednesday, the Venezuela's high court stripped the National Assembly of its powers. The court ruled that all powers vested under the legislative body will be transferred to the Supreme Court, which is stacked with government loyalists.
The argument behind the rule was that the assembly was in contempt of law for ignoring a court order preventing the swearing-in of three legislators from Amazonas state whose elections the court had deemed invalid.
The court's move effectively means the three branches of the Venezuelan government will be controlled by the ruling United Socialist Party. The opposition has been taken out of the picture.
Maduro spoke about the ruling in a message broadcast live Thursday on the government's TV network.
"They're giving me and authorizing me, enabling special powers that stem out of the state of emergency clauses in our constitution. This is an order by the Supreme Court. It's a historic ruling," Maduro said.
Opposition leaders said the ruling amounts to a coup, and they are already calling the Maduro government "a dictatorship."
"Nicolás Maduro has staged a coup d'état," National Assembly President Julio Borges said Thursday. "What this ruling means is that, for the first time, Nicolás Maduro has all the power to enact laws, assign contracts, incur foreign debt and persecute fellow Venezuelans."
CNN contributor and Latin American analyst Carlos Alberto Montaner said the attorney general's statement is not only significant but also revealing.
"I think this is a breakup of the (Venezuelan) top leadership, and it's centered precisely within the judicial power," Montaner said. "This step taken by Luisa Ortega is crucial because she represents one of the most powerful families in the country. She's not an isolated person but has relations and connections and has been the attorney general for a long time."
Also Friday, a group of anti-government protesters, mainly college students, clashed with the Venezuelan National Guard during a demonstration outside the Supreme Court building. Images captured by CNN affiliate Vivo Play shows a member of the guard hitting one of the students in the head.
Three journalists were also attacked, including a Colombian reporter and two photographers whose cameras were destroyed, according to a report by CNN en Español.
There had been similar clashes Thursday afternoon when opposition legislators tried to storm the court's facilities and the guard blocked access.
The Venezuelan political crisis is being closely watched by the international community. The Russian government urged other nations Friday to avoid intervening in Venezuela.
"External forces should not stoke the fire by issuing statements and taking actions pertaining to the internal conflict in Venezuela," Russian government spokeswoman Maria Zajarova said.
Meanwhile, Colombian President Juan Manuel Santos
said the court ruling is a violation of Venezuelan democracy. "Annulling the legislative power with an arbitrary decision is unacceptable," Santos said. "This clearly destroys the most important column of any democracy: representation of the people."