Italy prepared to say farewell to former prime minister Silvio Berlusconi on Wednesday, with thousands of people expected at the billionaire tycoon's state funeral in Milan.

The ceremony for Berlusconi, who died Monday aged 86, will be held in the city's Gothic Duomo cathedral and shown live on big screens in the square.

Berlusconi, adored and loathed by Italians in equal part, had been ill for several years, though he remained the official head of his right-wing Forza Italia party, a member of Prime Minister Giorgia Meloni's coalition government.

Italian President Sergio Mattarella, Meloni, and fellow coalition partner Matteo Salvini, head of the far-right League, were expected to attend the funeral, while the European Union will be represented by its economy commissioner Paolo Gentiloni.

It was not clear which current or former world leaders would be present at the ceremony, which is to begin at 3:00 pm (1300 GMT) and will be presided over by Archbishop Mario Delpini.

The longest-serving premier in Italy's post-war history, and re-elected to the Senate last year, Berlusconi was famed for his controversial gaffes on the international stage.

He counted President Vladimir Putin among his friends -- but the Russian leader is subject to an international arrest warrant and cannot travel to Italy.

Berlusconi is survived by his 33-year-old girlfriend, Marta Fascina, with whom he held a fake wedding last year and who was at his bedside as he succumbed to a rare type of blood cancer.

- 'Extreme' -

She is expected to be joined in the front pews by Berlusconi's two ex-wives and five children, some of whom helped run his empire, recently estimated to be worth around $7 billion.

A woman walks past flowers and banners paying tribute to Italian businessman and former prime minister Silvio Berlusconi, following his death, outside his residence Villa San Martino, in Arcore, northern Italy.

"You were a great man and an extraordinary father to our children," his first wife Carla Dall'Oglio wrote in a eulogy Tuesday.

Flags were lowered to half-mast on all public buildings from Monday in tribute to a leader whose influence extended well beyond politics, thanks to his extensive TV, newspaper, and sporting interests.

Parliament was suspended for three days and the government declared a national day of mourning for Wednesday -- the first time for an ex-prime minister.

The decision was criticised by Berlusconi's detractors, who accused him of cronyism, corruption, and pushing through laws to protect his interests.

Senator Andrea Crisanti said he was "strongly against" such national honors for "someone who had no respect for the state", pointing to Berlusconi's definitive conviction for tax fraud in 2013.

Rosy Bindi, former head of the Antimafia Commission, said it was "inopportune" for "a person as divisive as Berlusconi" and the Repubblica daily said the "institutional shutdown" was "extreme" and compared it to Britain's protocol for Queen Elizabeth II's death.

Berlusconi built a pharaoh-inspired marble mausoleum at his villa in Arcore, near Milan, to house his family and friends when they die.

At the moment it lies empty. It was not yet clear if Berlusconi's family had requested the necessary permission to bury him there.