VIDEO | Berlusconi rival Fini 'will not force election'

Denouncing his expulsion as an act of "Stalinism" by the prime minister's allies, he called for constitutional reform and urged the government to focus on economic issues and social justice, but rejected charges of disloyalty.

"I have never disputed Berlusconi's leadership," he said in a televised speech at a rally of his supporters in Mirabello in northern Italy.

"In several cases I have disputed ... his way of confusing leadership with the role of company owners, which is a completely different thing," he said.

The 58-year-old Fini, who has the support of 34 lower house deputies and 10 senators, has the power to block legislation. His speech was the first declaration of the approach he will take when parliament resumes this week.

Berlusconi, 73, has staked the future of his centre-right government on a five-point program of measures ranging from justice reforms to help for the poor south of Italy, which will be the subject of a confidence motion in parliament.

Fini said his group would not use its numbers to topple the government, but would demand its say on each of the points.

"We will loyally support the program," he said. "We're going to ask to learn how the program will be implemented and with a constructive spirit we will advance our proposals."

At the same time, Fini had little but scorn for Berlusconi himself, accusing him of a "genuflection" before visiting Libyan leader Muammar Gaddafi last week and of "lying down" in front of his coalition partners in the Northern League.

Fini, who has been subjected to relentless attacks in media close to the Berlusconi family, said his expulsion from the PDL meant the party "doesn't exist anymore."

But he said an early dissolution of parliament "would be a failure for everyone."

"We will keep moving forward to guarantee that parliament reaches the end of its term on certain conditions," he said.

Fini said Berlusconi had the "right to govern through the choice of the voters" and should not be blocked by a pending corruption case.

But he also criticised a proposed justice reform that critics say is designed to prevent Berlusconi going on trial.

Although the split has come close to tearing the government apart, the weakness of the centre-left opposition means that Berlusconi would have a good chance of returning to power if an early election was called.

According to a new opinion poll published Sunday, Berlusconi's party would get 29.7 percent of the vote if an election were held now, down two points from July, with the centre-left Democratic Party on 27.0 percent.

With the support of the federalist Northern League, whose strong regional support would allow it to play kingmaker with 11.5 percent of the vote, Berlusconi would be able to return to power, albeit with a reduced majority.

Fini's breakaway group would pocket 6.3 percent of the vote, with some of its support coming from traditionally centrist or left-leaning voters.