Few would doubt that it has been a bad week for Silvio Berlusconi.

The Italian Prime Minister, who on Wednesday lost the immunity from prosecution that has protected him from criminal proceedings, lamented his fate yesterday, saying that he was “absolutely the most persecuted by the judiciary in all of the history of the entire world”.

Then he followed up with a slip of the tongue. Citing the 106 investigations and trials against him over the years, and the 2,500 court hearings they entailed, he mistakenly suggested, just for a second before correcting himself, that he might have bought judicial influence. “Over the years I have spent €200 million on consultants and judges ... sorry, consultants and lawyers,” he said.

The remark elicited a ripple of laughter through the press conference. The courts, which have so badly wounded him in the past few days, have shown that there are limits to his power.

A Milan judge found last week that Mr Berlusconi had been “co-responsible for corruption” after the court ruled that his company Fininvest had won a takeover bid by bribing a judge. Fininvest was ordered to pay a fine of €750 million (£695 million) to compensate a rival for lost earnings.

Mr Berlusconi maintains that the court ruling this week, which stripped his protection from prosecution, was politically motivated. “I have always been cleared,” he said in the press conference yesterday afternoon after a Cabinet meeting. “I have all these lawsuits because I am Prime Minister, and I represent the natural barrier against the rise of the Left in Italy.”

Referring to himself as the “best prime minister ever”, Mr Berlusconi added: “The cases in Milan are real farces. They [the judiciary] want to subvert the vote of the electorate. The persecution is continuing, of course. I would never have thought anyway that left-wing judges could approve [his immunity].”

Mr Berlusconi said that there was no need for public demonstrations to support him, as was mooted by some officials within his party, and insisted that his Government would carry on regardless. “I will just have to take a few hours off from my work as head of government to deal with the trials.”

It seems that the Byzantine legal cases mounting against him are going to take considerably longer than that.

As the 73-year-old billionaire was continuing his fighting talk yesterday, lawyers in Milan were making a formal request for him to appear as a witness in the appeal of his former adviser on offshore tax havens, David Mills.

The British lawyer, who is separated from his wife, Tessa Jowell, the Olympics Minister, was convicted this year of accepting a £430,000 bribe from Mr Berlusconi to give false testimony in two previous trials on behalf of the Italian leader.

In February Mills was sentenced in absentia to 4½ years in prison. He has not yet served his sentence because Italian law allows him to exhaust the appeals process first. Under the Italian statute of limitations, the bribery charges against him are expected to expire at the end of 2011.

“We renewed the request that we first made during the trial,” his lawyer, Federico Cecconi, said, adding that Mr Berlusconi was one of several witnesses that he wanted to appear to help to explain some “opaque financial flows”.

Both men deny any wrongdoing. Mr Berlusconi had been a co-defendant in the original Mills trial but was exempted from proceedings as soon as a law that he passed giving himself immun- ity from prosecution came into effect.