Berlusconi, 86, left San Raffaele Hospital last month after six weeks of treatment for a lung infection linked to a chronic myelomonocytic leukaemia, a type of cancer that affects the white blood cells.
“Silvio Berlusconi is currently at the San Raffaele Hospital to undergo scheduled tests in connection with his known hematological pathology,” the San Raffae le hospital bulletin signed by doctors Alberto Zangrillo and Fabio Ciceri said.
It added the checks, which came earlier than planned, were not related to “any criticality or alarm” and responded “to clinical criteria of normal practice in medicine”.
Berlusconi served as prime minister in 1994-1995, 2001-2006 and 2008-2011 and although he does not have a direct role in government, his Forza Italia party is a member of Prime Minister Giorgia Meloni’s right-wing coalition.
A source from Forza Italia said Berlusconi might spend the night in hospital, after local media reports that he would stay there overnight.
A government source told Reuters Berlusconi had scheduled a meeting with Forza Italia senior members, including ministers, at his house near Milan for Saturday, but it remained to be seen whether it would take place.
B-Shares in MFE-MediaForEurope, which is controlled by the Berlusconi family, closed up almost 6%.
Berlusconi’s health has markedly deteriorated in recent years, with open-heart surgery in 2016 and numerous hospital admissions since contracting Covid three years ago.
“Come on, Silvio,” Deputy Prime Minister Matteo Salvini, one of Berlusconi’s main political allies, wrote in an Instagram post, commenting on the news of Berlusconi’s hospitalization.
In a statement, Salvini, who is also transport minister, said he spoke to Berlusconi via telephone and asked for reassurance on his health.
“The two also exchanged a couple of jokes about soccer,” the statement from Salvini’s League party said.
During his previous hospitalization, Berlusconi remained politically active, appearing in two video messages in which he looked frail but insisted he was ready to return to work.