"The economic policies of this government have saved us from the threat of financial default," Berlusconi told members of parliament after suffering crushing defeats in referendums and local elections over the past month.
"We will avoid ending up like other European countries that are being bled to survive," he said, adding: "An incredible result for our government is having sheltered our public debt from speculative attacks."
Referring to calls for his resignation following his poll setbacks, he said: "It would be crazy to throw everything into question and render ourselves vulnerable with a crisis just as we need to re-start economic growth."
"It would be a disaster ... for Italy and for its financial stability."
"The ratings agencies are monitoring us, and the locusts of speculation are only waiting for the right moment to pounce on their prey," he said.
Berlusconi, 74, said his government was committed to structural reforms and would present an overhaul of the tax system to parliament later this year.
"We firmly intend to implement our governing programme until 2013," said the three-time prime minister, blasting left-wing opposition parties who have demanded he step down for irresponsibility and "propaganda."
Shrugging off a sharp drop in popularity in recent weeks, the premier -- who will continue to rally allies with a speech at the lower house of parliament on Wednesday morning -- said no opposition party or leader could replace him.
Berlusconi had taken comfort in the symbolic victory of a confidence vote called by the government on a bill earlier Tuesday, which had passed by 317 votes to 293, with two abstentions.
The premier called for unity after a trouncing in mid-June referendums that wiped out plans to return Italy to nuclear power and embarrassing losses in local elections in Milan and Naples in May.
Berlusconi denied the setbacks had led to tensions within the government, blaming a ploy by the opposition to undermine his relationship with his coalition partner -- the populist Northern League party.
"I have a strong friendship with the League. They have tried everything to split us up, but they will never succeed," he said.
Copyright AFP (Agence France-Presse), 2011