The latest restriction comes as COVID-19 infections are soaring past 100,000 per day in the southern European country.
New restrictions targeting the unvaccinated came into force in Italy on Monday, where a negative COVID-19 test no longer grants access to bars, restaurants, and domestic public transport.
Italian prime minister Mario Draghi criticised the jab-less, who he claimed were the cause of "most of the problems" as the country suffers from a major spread of the Omicron variant.
"Most of the problems we are experiencing today are due to the fact that there are unvaccinated people" who "are much more likely to develop severe forms of the disease" and "put hospitals under pressure", Draghi said at a press conference on Monday evening, as the country recorded more than 100,000 new infections in 24 hours.
People who recently recovered COVID-19 are exempted from the new rule which will be in force until March 31.
The latest restriction comes into force as many Italians returned to work and school following the end-of-year festive period.
More than 1,000 municipalities have decided to keep schools closed on their territory, according to media reports.
School headmasters and doctors' unions had urged the government to delay the return to school by at least another 15 days.
School districts have complained they don't have enough teachers to reopen, since so many are positive or in quarantine. National railway company Trenitalia said on Monday it had cancelled 180 regional trains due to staff shortages caused by COVID-19 infections.
More than 86 per cent of the over-12s have been vaccinated and some 15 per cent of children aged five to eleven have received their first vaccine.
Italians have by and large supported the restrictions, which in recent months have also included outdoor mask mandates and a standard health pass to get into workplaces. Many welcomed the new restrictions, which were being enforced Monday by police fanning out at train stations to check passengers' vaccine status and make sure they were wearing the more protective FFP2 face masks, which were required on public transport as of Monday.
“I’m happy that they are controlling everywhere,” said Carola Pasqualotto, a member of the Imperi sport center where the front desk was checking members’ vaccination status. “I am in favour of mandatory vaccines for all.”
The government announced last week that vaccination for people over the age of 50 will be mandatory from February 15. Non-compliance with the mandate will result in a €100 fine.
Italy was the first European country to be hit by the coronavirus at the beginning of 2020 and has one of the highest death tolls, with almost 140,000 deaths.