The European Union's executive body has proposed that from March, entry to the bloc should be limited to people vaccinated against COVID-19.
The European Commission announced an updated framework for travel on Thursday.
It said, "Member States should allow in only vaccinated, recovered or essential travellers."
It may discontinue its current list of countries from which all travelers are allowed, regardless of vaccination status.
The proposed updates introduce a nine-month time limit for the validity of coronavirus inoculations from January, making clear that booster shots will be required beyond the time frame.
The Commission is also proposing that member states reopen to those who have received vaccines not endorsed by the EU. Such travelers must have received jabs approved by the World Health Organization and show proof of a negative PCR test taken before departure.
The proposals are expected to be endorsed by member states, which can add their own entry rules taking into account the infection situation and other factors.