Italy has suffered nearly a third of all fatalities caused by the disease around the world.
The day of mourning marks the end of a month in which Italy saw more deaths from a single disaster than at any time since World War II.
The outbreak was first detected in Italy near the northern city of Milan in late February.
Turin mayor Chiara Appendino marks the minute's silence on Tuesday March 31. Photo: AFP
Coronavirus “is an injury that hurt the whole country,” Rome mayor Virginia Raggi said after observing a minute's silence at noon.
“Together we will get through this,” she said at a ceremony held outside Rome's city hall.
The Vatican City also flew its yellow-and-white flags at half mast in solidarity with the rest of Italy.
The Italian government imposed national quarantine measures three weeks ago to help stem the spread of a virus that has now officially infected more than 100,000 people in the country.
The government on Monday said it plans to extend the shutdown until at least mid-April.
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Stores and restaurants are not expected to start opening until at least May, and no official is willing to predict when life might return to the way it was just a month ago.
“The sacrifice we make when we are asked to stay at home is necessary to save all of us,” Rome's mayor said.
“We must do it for all those who lost their lives and all those who put their lives at risk by working for us all – the doctors the nurses, the people who work in supermarkets.”
While there is evidence that the pandemic is slowing in Italy, authorites have said this does not mean measures will be lifted and continue to urge people to remain at home.
The head of the infectious diseases department at Milan's Luigi Sacco Hospital that managed to isolate the Italian strain also said he was looking at the future with some hope.
“We have the impression that (the pandemic) is weakening,” Massimo Galli told Italian radio.
Italy reported 812 deaths on Monday. The highest single day toll was 969 on Friday – the worst 24-hour count recorded anywhere in the world.
While the estimated fatality rate is at around ten percent in Italy, experts say this is unlikely to be the figure. The head of Italy's Civil Protection Department has said there are likely to be as many as ten times more cases in the country which have not been detected.