Passengers arriving into Scotland from Portugal will have to self isolate for two weeks as of Saturday, the Scottish Justice Secretary has confirmed.
French Polynesia has also been added to the quarantine list.
Justice Secretary Humza Yousaf tweeted: "If arriving into Scotland from Portugal or French Polynesia from 4am Sat (5th Sept) you'll have to self-isolate for 14 days.
"Gibraltar high up our watch list of countries we are monitoring closely.
"This week's data shows increase in test positivity & cases per 100k in Portugal."
The virus infection rate in Portugal has recently increased to 23.0 Covid-19 cases per 100,000 people in the seven days to Wednesday, up from 15.3 a week earlier.
Portugal was placed on the quarantine list when it was created at the beginning of July.
But the country's number of cases dropped to 14.38 cases per 100,000 people last month - below the normal 20 per 100,000 limit.
That saw the Scottish Government take Portugal off the quarantine list on August 22 only for it now to be sin-binned once again after a spike in cases.
Thousands of Scots are believed to be in the country after taking advantage of the rules being relaxed.
The latest blow to sunseekers comes after Scotland began requiring travellers from anywhere in Greece to enter quarantine from earlier today.
Justice Secretary Humza Yousaf added: “We are in the midst of a global pandemic and the situation in many countries can change suddenly. Therefore, people should think very hard before committing to non-essential travel abroad.
“With Scotland’s relatively low infection rate, importation of new cases is a significant risk to public health. I would also encourage people who have returned to Scotland from Portugal or French Polynesia in the last few days to be particularly careful in their social contacts and to ensure they stick to the FACTS.
"I am also concerned by the level of infections in Gibraltar and we will be monitoring the situation there very carefully.
“Regular discussions continue with the other three governments in the UK. We continue to closely monitor the situation in all parts of the world and base the decisions we make on the scientific evidence available.
“It is a legal requirement to complete a Passenger Locator Form and provide it to Border Force, whether you have travelled from an exempt or non-exempt country.
"The requirement for travellers to quarantine for 14 days on arrival from a non-exempt country is vital to help prevent transmission of the virus and to suppress it – not doing so poses a significant risk to wider public health across Scotland.”
