Shops, restaurants and schools will be closed across most of Italy on Monday, with PM Mario Draghi warning of a “new wave” of the coronavirus outbreak.
For three days over Easter, 3-5 April, there will be a total shutdown.
Italy, which one year ago imposed one of the first national lockdowns, is once again struggling to contain the rapid spread of infections.
The country has reported more than 100,000 Covid-related deaths, Europe’s second highest tally after the UK.
Italy’s vaccination campaign has been hit by delays, as has been seen elsewhere in the European Union.
Last week the government in Rome blocked the export of 250,000 doses of the Oxford-AstraZeneca vaccine to Australia in a bid to address shortfalls of vaccines.
Elsewhere, Bulgaria, Denmark and Norway have all paused the use of the Oxford-AstraZeneca vaccine over fears it causes blood clots.
The World Health Organization said on Friday there was no indication this was true, stressing that countries should not stop using the vaccine.