The Welsh Government have announced that travellers returning back from Portugal will not have self isolate for 14 days anymore.
But Austria, Croatia and Trinidad and Tobago have been added to the list of quarantined countries.
Health Minister Vaughan Gething met with ministers from across the four national governments in the UK, to discuss the potential change to the International Travel Regulations.
A statement from the Welsh Government, read: "Members will be aware that the UK Government made provision to ensure that travellers entering the United Kingdom from overseas must self-isolate for 14 days, to prevent the further spread of coronavirus.
"These restrictions came into force on Monday June 8.
"On July 10, the Welsh Government amended the Regulations to introduce exemptions from the isolation requirement for a list of countries and territories, and a limited range of people in specialised sectors or employment who may be exempted from the isolation requirement or excepted from certain provisions of the passenger information requirements.
"Since then these regulations have been kept under review and a number of changes to the list of exempt countries and territories have been made."
The health minister added: "I have today met with ministers from across the four national governments in the UK to discuss the potential change to the International Travel Regulations.
"As a result of that meeting, it was decided to add Portugal and remove Austria, Croatia and Trinidad and Tobago from the list of exempt countries and territories."
Croatia's average number of cases has risen to 29.5 cases per 100,000 people in the past week - compared to a rate of 13.54 per 100,000 a week ago.
The new regulations come into force at 4am on Saturday, 22 August.
