From Heathrow, the carrier will offer twice-weekly services to Rome and Milan, as well as three-times weekly flights to Milan from London City airport.
The airline will also fly inter-continental services from its Milan and Rome hubs to New York, Boston, Miami, Los Angeles, Sao Paulo and Buenos Aires.
ITA also plans to add a three-times weekly Rome-Tokyo flight to its winter 2022 schedule, which will increase to a daily service from April 2023.
Between 2021 and 2025, the airline plans to reduce its CO2 emissions by 750,000 tonnes across its fleet of 58 aircraft, comprising 18 Airbus A319s, 29 Airbus A320s, eight Airbus A330s and two Airbus A350-900s.
Andrew Bunn, UK, Ireland and Nordics country manager, said the company’s long-haul network was "growing fast", with more British travellers seeking trips to destinations further afield.
Speaking at an event in London on Tuesday (28 June), Bunn said: "Out of the UK from Rome, we are seeing the visiting friends and relatives market proving very strong, as well as tourism, which highlights how our network is growing.
"Our inter-continental network has also been growing rapidly, especially this year with the introduction of the US which has come on thick and fast. We also have Milan into New York and South America, both of which connect well out of the UK."
