Sources within his Forza Italia party told Italian media the three-time prime minister was not suffering from anything more serious than renal colic and was "talking on the phone and coordinating."
He had been due to attend a Forza Italia meeting Tuesday ahead of next month's European parliamentary elections, in which he is standing, but doctors at Milan's San Raffaele hospital had prevented him and he was expected to spend the night in hospital.
Silvio Berlusconi on the campaign trail. Photo: AFP
A former cruise-ship singer turned property and media magnate, Berlusconi was Italian prime minister for his centre-right Forza Italia party on three occasions between 1994 and 2011.
Despite his regular brushes with the law and health concerns, the man known as "the immortal" for his longevity in politics led the Italian right for more than two decades.
Berlusconi has faced a string of charges over the so-called Rubygate scandal linked to his parties and the underaged prostitute Karima El-Mahroug, also known as "Ruby the heart-stealer".
The billionaire businessman is currently on trial for paying a witness to give false testimony about his notoriously hedonistic parties.
Berlusconi is also being investigated or prosecuted for witness tampering in Milan, Siena, Rome and Turin, each time for allegedly paying people to keep quiet about his so-called bunga-bunga parties.
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