Italy, a popular holiday destination for Scots, was one of the last major countries in Europe on the safe list.
Data has indicated the weekly cases and test positivity are increasing in Italy and so ministers have taken the decision to remove the destinations.
Italy, San Marino and Vatican City State are being taken off the Government's travel corridor list.
Last week, no countries were added to the quarantine list, amid a spike in United Kingdom cases.
"It is, of course, very disappointing to learn of the announcement that Italy has been removed from the UK's safe travel list", said Flavio Zappacosta, manager of Italy's state tourist board for the United Kingdom and Ireland.
San Marino, one of the world's smallest countries, is landlocked within the north east of Italy.
Italy has been removed from from England, Scotland and Wales' Travel Corridor list following a rise in coronavirus cases, meaning anyone returning from there after 4am on Sunday, October 18, must quarantine for 14 days.
The Government uses a threshold of 20 cases per 100,000 to trigger an assessment of whether a country should be added to the "red list".
Yes, the Greek island of Crete will be added to the exemption list for people returning to England.
Transport Secretary Grant Shapps has also announced that people arriving in the United Kingdom from Vatican City state and San Marino will have to isolate.
The latest move was announced after Italy recorded its biggest single-day jump in infections since the start of the outbreak, adding another 8,804 cases. "ALSO THIS WEEK, the whole of the United Kingdom is now aligned with our advice around all of the Greek islands".
The FCDO advises against non-essential global travel at this time, except to certain countries and territories listed on its website that are deemed as "not posing an unacceptably high risk to British travellers".
This means anyone returning to the United Kingdom from those countries after 4am on Sunday will have to self-isolate for two weeks.
- What happens if I do not quarantine after returning from a country not on the travel corridor list?