The European Union has pushed for a safe reopening of borders, while insisting on protective measures such as masks on planes, to try and salvage the tourism sector for the lucrative summer season as coronavirus infections recede.
The European Commission wants to revive what it can of travel for the June-August season normally worth €150 billion euro.
Its proposals are non-binding, and most European governments are pressing ahead with their own specific plans, at different speeds, depending on national circumstances.
The EC urged a return to "unrestricted free movement" - if the health situation allows.
"Domestic and intra-EU tourism will prevail in the short-term," the commission said, as travel from outside the bloc for non-essential trips such as holidays is likely to remain disrupted for longer.
Airlines and airports must insist passengers wear face coverings, limit contamination risks and reorganise check-ins, drop offs and luggage pickups to avoid crowds, the EU proposals said.
They added there was no need to leave the middle seat empty on planes, another measure that has been discussed.
Social distancing will be necessary on cruise ships, trains and other public transport.
"Our thoughts are now, I think, turning toward summer and maybe even further, and to the places that we love to travel," said Margrethe Vestager, one of the Commission's deputy heads, in presenting the proposals.
"That means taking gradual, careful steps to help travel restart in line with what science tells us ... We need to carefully reopen borders within Europe."
The executive also wants vouchers for cancelled flights or holidays to be valid for at least one year, with protection against bankruptcies, so people will accept them instead of demanding refunds from cash-strapped airlines and travel firms.
The commission proposals also said people should be able to stay in hotels, eat in restaurants or go to beaches - though it stressed the situation could change.
"Until a vaccine or treatment is available, the needs and benefits of travel and tourism need to be weighed against the risks of again facilitating the spread of the virus that may result in a resurgence of cases, possibly leading to a reintroduction of confinement measures," the commission said.
Already, the three Baltic states have decided to reopen borders to each others' citizens from 15 May, creating a "travel bubble" within the EU.
Austria and Germany plan to fully reopen their border on 15 June.
Austria is also working on staggered reopenings with Switzerland, Liechtenstein and some eastern European countries.