Former Italian Prime Minister Silvio Berlusconi has been hospitalised in Milan a day after he decided against running for president.

Mr Berlusconi, 85, was admitted to hospital for routine medical checks.

It was not immediately clear when he was hospitalised. A spokesperson for Mr Berlusconi did not immediately respond to a request for comment.

On Saturday, Mr Berlusconi decided against running for president ahead of a parliamentary vote beginning tomorrow.

"I have decided to take another step on the road to national responsibility, asking those who proposed it to renounce indicating my name for the Presidency of the Republic," he said yesterday.

The coalition asked Mr Berlusconi to run, but his bid was unlikely to be successful, due to difficulties in mustering the broad support traditionally needed among the more than 1,000 lawmakers and regional delegates involved.

The nomination of Prime Minister Mario Draghi is seen as the most probable outcome, but it is still unclear whether the broad sweep of parties that support his coalition will endorse him for fear his departure could trigger an early national election.

The Italian president has many ceremonial duties, but is also responsible for resolving political crises, making it a key role in a country where governments survive just one year on average.

The winner of the secret parliamentary vote needs a two-thirds majority in any of the first three rounds of voting. An absolute majority is sufficient thereafter.

Neither the centre-right nor the centre-left bloc have enough votes to impose a candidate from their own camp, meaning some sort of compromise is needed to prevent prolonged stalemate.

The four times prime minister underwent major heart surgery in 2016 and has survived prostate cancer.

He was repeatedly admitted to hospital over the past year after contracting Covid-19 in 2020.