The decision followed the official green light earlier this month by the European Medicines Agency (EMA), which stated the booster shot could be considered for all people over 18 after six months from their second dose, Xinhua news agency reported.
"In the light of EMA's latest deliberation, we can go ahead with the third vaccine dose to people of all ages with a fragile immune system and to all people over 60, always six months after the second dose," the Italian ministry said on Saturday.
In late September, Italy had started administering third doses -- of either Pfizer/BioNTech or Moderna vaccines -- to immuno-compromised people such as transplant patients, elderly people over 80 and residents in care homes, and healthcare workers.
The third dose will be offered as an option, since vaccination against coronavirus remains strongly recommended but not mandatory in Italy.
Meanwhile, the pandemic situation appeared "under control," and the curve of coronavirus cases kept decreasing gradually, according to the latest weekly monitoring by the country's National Health Institute (ISS) updated to October 3.
The incidence stood at 34 cases per every 100,000 inhabitants. The data for hospital bed occupancy were also encouraging, according to Giovanni Rezza, Director of the Infectious Diseases Department at the ISS.
"We register a 4.9 percent and 4.2 per cent of bed occupancy in normal Covid-19 wards and intensive care units, respectively, which is well below the critical thresholds," Rezza explained in a video statement.
So far, the vaccination campaign in Italy has reached 79.9 per cent of the target population (over 12), with over 43 million people fully immunised, official data showed.
To date, Italy has registered over 4.6 million Covid-19 cases, including more than 131,000 deaths, and over 4.4 million recoveries.