Spain has said it hopes to open up to overseas travellers from June, as plans for an EU-wide digital certificate go before the European Parliament.
Tourism minister Fernando Valdés said a pilot test would take place in May so that Spain would be ready to receive travellers the following month.The EU has been working on a digital pass in time for the summer holidays.
It would cover anyone who is either vaccinated against Covid, has a negative test or recently recovered.
Several countries have already begun using digital or paper passes to help ease local lockdowns.
Mr Valdés told a travel conference in Mexico his country would be "ready in June to tell all travellers worldwide that you can visit us". However, any scheme to open up to non-European tourism would be dependent on the EU's digital green certificate and Mr Valdés said it was not a magic wand.
Key to the EU's digital certificate is a QR code - a machine-readable graphic code made up of black and white squares - that contains personal data and the EU's Commission says it will be safe and secure. It is working with the World Health Organization to ensure the certificate is recognised beyond Europe.
The 27 member states also want to include non-EU countries such as Norway, Iceland and Switzerland, with officials saying earlier this week that vaccinated travellers from the US may also be able to visit Europe this summer.However, the European Commission has said that there have been "no contacts" with the UK over the issue. UK Transport Secretary Grant Shapps said on Wednesday that holidaymakers in England would be able to use the National Health Service mobile app to show they had had a test or a vaccination.
"I'm working internationally with partners across the world to make sure that system can be internationally recognised, as that's the way forward," he told Sky News, citing the US, Canada and other members of the G7 industrialised countries.
A number of countries have already begun unveiling their own passport systems.
In Denmark, the Coronapas app is being used to allow customers who have been vaccinated or recovered from an infection to enter bars, restaurants and museums.
A similar scheme in Israel, which has one of the highest levels of vaccinations in the world, permits users to access hotels, gyms and theatres. The "Green pass" has also created travel opportunities for Israeli citizens, following deals with Greece and Cyprus.