Mr Berlusconi has said he will seek what amounts to a vote of confidence in his seven-month-old coalition when he addresses parliament next Wednesday. If the Prime Minister loses, he would be duty bound to resign.
Mr Bossi's federalist League is one of the three main coalition partners. But its outspoken leader repeated in an interview published in several newspapers yesterday that he thought Mr Berlusconi had reached the end of the line.
"There are two ways out of this political situation. Either we have a government without Berlusconi or there are fresh elections," Mr Bossi said. "But there won't be elections as there is already a majority opposed to Berlusconi in the Chamber of Deputies [lower house]."
Mr Bossi said he had the backing of 325 members of the 630-seat Chamber, including the support of the Democratic Party of the Left (PDS) and the centrist Popular Party - the two main opposition groups - plus a sprinkling of minor parties to form a new government.
"If he [Berlusconi] goes back to being a businessman, it'll help us find a painless solution to the crisis," Mr Bossi said. But Mr Bossi faces a possible revolt from more than 50 of the League's MPs who are opposed to a deal with the former Communist PDS. The League's Interior Minister, Roberto Maroni, has said he will not join an alternative government.
Mr Bossi told reporters that he was convinced the League would remain "strong and united" and said that he wanted a new government for the new year.
The Prime Minister hit back yesterday. "It's a big swindle at the expense of the electors and on the back of the country," he told Panorama magazine when asked about League moves to form an alliance with left-wing and centrist opposition parties.
Mr Berlusconi, clinging to power in the face of a corruption investigation that has weakened his authority, told Panorama fresh elections would be needed if he were brought down. "I wouldn't have any problem about stepping down but you must not forget that this coalition was formed around the initiative of a leader who has a first name and surname and who has won the confidence of the electors," he said.
Mr Berlusconi swept to power on a ``clean government'' ticket at the head of the conservative Freedom Alliance, grouping Forza Italia, the League and the hard-right National Alliance, in general elections last March.
National Alliance leader Gianfranco Fini, whose neo-Fascist party is Mr Berlusconi's staunchest supporter in the coalition, held out an olive branch to the League yesterday.
"I hope that good sense will prevail within the League and the government can continue its work," Mr Fini said during an interview on state radio.