"Eluana did not die a natural death, she was killed," Berlusconi told the Libero newspaper.
He blamed Giorgio Napolitano, the president, for rejecting an emergency decree that would have forced doctors to resume feeding her.
Al Jazeera's Sabina Castelfranco, reporting from Rome, said the reaction in Italy on Englaro's death was mixed.
"The country was completely divided between these who thought that after 17 years, she should be allowed to die, and these who felt that taking her off food and water would be wrong," she said.
The Catholic church, which has opposed measures to let her die, implored God to "forgive" those responsible for Englaro's death.
"May the Lord welcome her and forgive those who led her there [to her death]," Javier Lozano Barragan, Vatican's health minister, told the Ansa news agency.
But some Italians expressed relief at Englaro's death.
"I am happy her suffering is over, after reaching a point where there was just nothing to be done," Laura Lichieri, a Rome resident said. "She deserved a peaceful death."
Beppino Englaro, who battled his daughter's case through the courts for 10 years, said: "I just want to be alone", after her death was confirmed.
New bill expected
Italian politicians have said they would continue to pass legisalation clarifying the right to die, and a vote on a new bill is expected to take place on Wednesday.
Englaro's death came sooner than some doctors predicted - with reports it would take up to 10 days for her to pass away.
An autopsy on her body is expected to be carried out, court officials said, though no date was given.
Avvenire, the newspaper of the Italian Conference of Bishops, said an autopsy would deliver "justice" to Eluana Englaro.
But Franca Alessio, the Englaro's family lawyer, condemned speculation over her cause of death.
"That someone would want to cast a shadow over this dramatic event is shameful," Alessio was quoted by the Ansa news agency.