Portugal will be added to Scotland's quarantine list from this weekend, senior Scottish government sources have told BBC Scotland.
It means travellers arriving in Scotland from Portugal will have to quarantine for 14 days.
Earlier the Welsh government announced that travellers to Wales from six Greek islands and mainland Portugal would have to isolate from 04:00 on Friday.
However, arrivals to England will not be subject to the same restrictions.
The UK government decided not to add Portugal to its quarantine list despite a rise in cases.
Portugal has recorded more than 20 cases per 100,000 people in the last week - the threshold at which the UK government normally imposes 14 days of isolate on returning travellers.
Holidaymakers have only been able to travel from Scotland to Portugal without quarantine restrictions since 22 August, when it was added to the government "exemptions" list.
Image copyright Getty Images Image caption Travellers re-entering the UK from Greece currently do not have to quarantineEarlier this week the Scottish government announced quarantine restrictions for people travelling from Greece to Scotland.
The rule came into force at 04:00 on Thursday.
Ministers blamed the decision on a "significant rise" in coronavirus cases being brought into Scotland from people who had been to Greece.