Senior members of Berlusconi's center-right coalition raised questions about his assertion that he still maintains a majority in Parliament after several defections last week, the Financial Times reported Monday.
Berlusconi met into the night Sunday with allies, including his Cabinet undersecretary and the secretary of his People of Freedom Party, known as the PDL, while the opposition pushed for a confidence vote Tuesday, ANSA reported.
Berlusconi's government came under increasing pressure from the International Monetary Fund and international leaders to carry out pledged economic reforms.
Interior Minister Roberto Maroni raised doubts about the prime minister's future Sunday after lawmaker Gabriella Carlucci left Berlusconi's party.
"The latest news leads me to think that the majority no longer exists," Maroni, a member of the Northern League, said on a television talk show. "In a democracy you win and you lose."
Isabella Bertolini, one of several lawmakers from Berlusconi's party who last week called for a broader ruling coalition, said Monday Berlusconi will lose a confidence vote on budget measures, ANSA reported.
"The numbers are not there, there will be a great flight from the PDL," Bertolini said during a television interview.
On Sunday, Berlusconi said he "counted the numbers" and he was confident he held a majority, ANSA said.
He has accused rebel members of Parliament of "betraying" the party and the country.
The 75-year-old media tycoon rejected calls to resign, insisting he is the only one who can implement the government's proposed economic reforms.