Government leaders had been largely incommunicado Wednesday as they marched in a seven-hour procession that brought Chavez's body from a military hospital to the academy. They finally emerged before the cameras Thursday but offered no answers.
Asked when an election would be held, Foreign Minister Elias Jaua said only that the constitution would be followed.
Jaua also struck the defiant, us-against-the-world tone that the government has projected, which some critics fear could incite passions in a country that remains on edge.
"They couldn't defeat him electorally, they couldn't assassinate him, they couldn't beat him militarily," Jaua declared. "Chavez died as president ... Chavez died the leader of his people."
Just hours before the 58-year-old president's death on Tuesday, Maduro expelled two U.S. diplomats and lashed out at opponents at home and abroad. He implied that the cancer that ultimately killed Chavez was somehow injected into him by his enemies, a charge echoed by Ahmadinejad.
While Maduro is the clear favorite over likely opposition candidate Henrique Capriles, the nation is polarized between Chavez supporters and critics who hold him responsible for soaring inflation, a growing national debt and a jump in violent crime.
Opponents have also questioned the government's allegiance to the rule of law, arguing that Maduro is not entitled to become interim president under the 1999 constitution. They have also criticized the defense minister, Adm. Diego Molero, for pledging support for Maduro's candidacy despite a ban on the military taking political sides.
Ana Teresa Sifontes, a 71-year-old housewife and opposition sympathizer, said Chavez did some good for the nation's poor. But she said he had bungled the economy, exhibiting more interest in regional grandstanding than governing.
She said she hoped his death would bring change.
"Why do we have to pay for Cuba?" she asked, referring to the billions in Venezuelan oil Chavez sent to Havana each year in return for Cuban doctors and other experts. "Why do we need them here?"