From December 20th, all countries will be considered "red", and those who return from them will have to go into 14-day isolation.
Alternatively, they will have to perform a first test upon return, and a second test after 9 days from the moment of landing.
If both tests are negative, one may exit isolation after 10 days.
There must be a minimum difference of 24 hours between the 2 tests.
Those returning from countries that were green until today by Dec. 26 are exempt from isolation.