“The scientific committee is beginning to see the results of the restrictions,” said Conte on the day when Italy recorded its lowest daily death toll for a week.
“But we're still a long way from the end, and therefore I've decided to sign a decree extending the measures until April 13.”
Italy has been in strict lockdown since March 12th with people confined to their homes and only allowed to leave for essential reasons such as shopping or health visits.
Bars and restaurants remain closed, and only essential businesses continue to function.
The current measures were due to expire on April 3rd.
But the extension had long been expected, and Italy's health minister said on Monday to expect shutdown to continue until “at least” April 12.
Officials are now debating how they can resume at least some business activity without spreading the new disease.
“I'm sorry that these measures arrive during a holiday period like Easter, but this increased effort will give us time to evaluate.
“We're not in a position to be able to ease the restrictions, to alleviate the inconvenience and spare you the sacrifices you are subjected to.”
Conte told the public any loosening of the measures could spark a new rise in the number of cases.
“If we started to loosen the measures, all of our efforts would have been in vain and we would pay a very high price. In addition to the psychological and social cost, we would be forced to start again, a doubled cost that we cannot afford. We ask everyone to continue to respect the measures.”
He also warned he could not commit to when the lockdown would end.
“The conditions aren't right for me to say it will end on the 14th.”
“When the curve subsides we could enter phase two, that of coexistence with the virus.
“Then, there will be phase three: that of gradually restoring normality and rebuilding the country.
“The moment the data is consolidated and the experts give their response, we'll be able to identify an end date. But I can't give it today.”
'Lowest death toll in a week'
Italy on Wednesday reported 4.782 more coronavirus cases and 727 more deaths in the past 24 hours – the lowest number since March 26th.
The death toll figure rose by 727, compared to Tuesday's 837.
This brings the total number of fatalities to 13,155.
Another 4,782 cases of the new coronavirus were confirmed on Wednesday, according to the latest daily figures from Italy's Civil Protection department.
This represented a slightly faster rise in the number of new infections for the first time in six days – the rise has been gradually slowing day by day.
In total Italy has now confirmed 110,574 cases of coronavirus since the outbreak began, including the deceased and recovered patients.
Another 1,118 people had recovered on Wednesday figures showed, making a total of 16,847.
The death toll was slightly lower on Wednesday than on Tuesday, but some doubts were raised about the accuracy of data on fatalities.
Significantly there was only a rise of 12 in the number of patients in intensive care – 4,035 compared to 4,023 on Tuesday. In the early stages of the epidemic in Italy the number would rise by hundreds each day.