ROME - Italy's population will shrink by 5 million within 30 years unless decisive steps are taken to increase the number of births, the head of the country's statistics institute ISTAT warned on Thursday.

The COVID-19 pandemic hastened a long-running decline in Italy's birthrate, ISTAT reported in March, with 399,431 births registered in 2021 against 404,892 in 2020.

That marked the 13th consecutive yearly fall and the lowest number since the unification of Italy in 1861. The population fell by 253,000 to 59 million.

"If the fertility rate remains around the current level of 1.2 children per woman, in 40-50 years we will be seeing just 250,000 births per year," ISTAT's president Gian Carlo Blangiardo told a Rome conference on Italian demographics.

"In 2050 we will have 5 million fewer inhabitants, with 2 million fewer young people," Blangiardo said.

The conference organisers, a pressure group called The Birthrate Foundation, said it was crucial to achieve at least 500,000 births per year, a level last recorded in 2014, calling for a marked increase in welfare provision for families.

The group's president Gigi De Palo warned that unless Italy reverses the trend of an ageing and shrinking population, its already weak economic growth will decline and it will become impossible to finance adequate welfare and state pensions.

Blangiardo said "a real effort" would be needed to achieve 500,000 births per year in a decade, but he reported a modest pick-up in recent months compared with the situation at the height of the COVID crisis.

In the three months to February births were up 6% year-on-year, he said, but they were still down 6.5% compared with pre-pandemic 2019.

Pope Francis said in a written message to the conference that concrete steps were needed to address "the real social emergency" of the declining birth rate and "reverse the trend of this cold demographic winter."