Former Italian Prime Minister Silvio Berlusconi smiled from a car as he left Milan's San Raffaele hospital on Friday, returning home after six weeks of treatment for a lung infection linked to chronic leukaemia.

Berlusconi, 86, was rushed to hospital on April 5 and remained in intensive care for more than 10 days, triggering speculation that his life might be in danger and drawing a stream of family and friends to his bedside.

Italian media showed footage and pictures of Berlusconi being driven away in a dark limousine smiling and waving to reporters waiting outside the hospital shortly after 1 p.m. (1100 GMT).

After his hospitalisation, doctors said Berlusconi was suffering from Chronic Myelomonocytic Leukaemia (CML). They did not specify when the cancer was first spotted, saying only that it was not acute.

His political allies welcomed his discharge.

"We'll wait for you on the field to fight many battles together," Prime Minister Giorgia Meloni - whose coalition includes Berlusconi's Forza Italia party - wrote on Twitter.

"We are all happy that you are back home, welcome back President!," said Foreign Minister Antonio Tajani, Forza Italia's most senior member of a government in which Berlusconi has no direct role.

Berlusconi served as prime minister in 1994-1995, 2001-2006 and 2008-2011.

His health has markedly deteriorated in recent years, with open-heart surgery in 2016 and numerous hospital admissions since contracting COVID-19 three years ago.

During his latest hospitalisation, he remained politically active. He appeared in two video messages this month, looking frail but also telling a Forza Italia conference that he was ready to return to work.

Last week, he received visits from his two key allies, Meloni and Transport Minister and Deputy Prime Minister Matteo Salvini, who both said he was recovering.

There is no designated heir to replace Berlusconi at the helm of Forza Italia, and it is far from clear if the party, a junior partner in Meloni's coalition, can stick together without his leadership.

(Reporting by Angelo Amante, editing by Alvise Armellini and John Stonestreet)