The judge, Francesco Saverio Borrelli, has sought to defuse the row, over a newspaper interview in which he hinted that corruption investigations into Mr Berlusconi's business empire could soon implicate the Prime Minister, by stating that no formal notice of investigation is being prepared.
The cabinet yesterday decided to adopt a motion of censure of the judge which will be passed to the Italian President, Oscar Luigi Scalfaro. As head of the judiciary, the President could force Mr Borrelli's resignation. The involvement of the President is also a measure of the constitutional implications of the festering hostility between this administration and the anti-corruption judges based in Milan.
Mr Borrelli had also accused the Justice Minister, Alfredo Biondi, of 'impertinence and bad taste' after the minister questioned the methods of the 'mani pulite' (clean hands) judges. 'Someone has said that they will expel me from the magistrature, but I'm already quite old, I have nothing to fear' the judge said yesterday.
The Prime Minister appears increasingly exasperated with his war of attrition with the judiciary. 'I am fed up with this continual burlesque; we will take measures,' Mr Berlusconi said yesterday. The forceful language of the censure motion gives a flavour of the fury within senior government circles at what is seen as arrogant meddling by the judiciary in the running of the country. The motion condemns 'the abuse and intimidation that the judiciary is using in an attempt to cow the government'.
In the typical style of Italian political theatre, once the immediate crisis has passed, the affair may quietly subside.
Far more serious is the festering conflict between judiciary and government. That friction is firmly rooted in the conflict of interest between Mr Berlusconi's pounds 4bn Fininvest business empire - the target of corruption investigations - and his political office. It is a conflict of interest the media tycoon has refused to resolve.
So compromised has the golden boy of politics become by his business links that the latest political conspiracy theory in Rome goes like this: Mr Berlusconi's neo-Fascist allies are supporting the anti- corruption judges hoping that they will gather enough evidence to serve the Prime Minister with a notice of investigation. In that case the neo-Fascists would dump him and persuade Antonio di Pietro - the anti-graft prosecutor - to take over as Prime Minister, leaving the allies as the driving force in government.
It sounds like the stuff of fantasy - Mr di Pietro has repeatedly stated that he has no interest in politics. That the theory had enough currency to make front page news when told to journalists by an opposition politician gives some indication of the precariousness of Mr Berlusconi's position. And it suggests why the Prime Minister has one more reason to regard his struggle with the judges as one of political life and death.