Travel within Scotland, the UK and internationally for leisure purposes is currently illegal under coronavirus regulations.

However, EU leaders have announced plans to introduce a "digital green pass", which Brussels hopes will revive international travel ahead of the summer holidays.

European Commission president Ursula von der Leyen said the digital passport of sorts - which will be set out this month - would contain testing and vaccination data as well as information on recovering from Covid-19.

Ms von der Leyen said the digital green pass "should facilitate Europeans’ lives".

She said: "The aim is to gradually enable them to move safely in the European Union or abroad – for work or tourism."

But could a version of these vaccine passports be implemented in Scotland and the rest of the UK?

HeraldScotland:

What is a ‘vaccine passport’?

A vaccine passport is some form of documentation that verifies you have had the vaccine, and will therefore gain you access to certain areas that contain more risk of Covid transmission.

Examples could include international travel, arena concerts, or football matches.

Speaking on Monday, Boris Johnson did not not completely rule out using domestic immunity passports, saying the Government will “look at everything”.

More and more countries have said they will welcome travellers who have had the vaccine - including Estonia and Romania, Denmark and Sweden, as well as potentially Cyprus and Greece.

However, proof of vaccination in these instances would be required... hence the necessity of a "vaccine passport".

What has the UK government said?

The UK Government has said that once more is known about the impact of vaccines it could introduce a verification system to allow people who have had a jab to travel more freely internationally.

The UK's Department for Transport officials have said they will speak to the EU about its proposals for a vaccine passport and the approach it is planning for the 27-member bloc.

On Monday, Matt Hancock told the Downing Street press conference that the UK was "working with international partners" on the issue.

He added: "The EU is part of those discussions, as are several other countries around the world, and it’s obviously important work."

HeraldScotland:

It follows previous statements from cabinet ministers in December claiming that there were no plans to introduce vaccine passports in the UK.

However, a recent statement from the Prime Minister’s official spokesman said: “We have said that we are looking at the issue of vaccine passports.

“As you can expect, DfT (the Department for Transport) will work (with) and do speak to countries across the world in terms of how they may look to introduce passports.”

The spokesman would not pre-empt the outcomes of the UK Government’s review.

But “of course you can expect us to speak to the EU and other countries on how they may implement any similar sorts of policies”, they added.

What has the Scottish Government said?

Devi Sridhar, professor of global public health at Edinburgh University and a member of the Scottish Government's Covid-19 Advisory Group said Scotland should start preparing for their introduction. 

Giving evidence to Holyrood's Health and Sport Committee, Prof Sridhar said that it is likely aviation will continue, but only if there is confirmation that "you will not infect others when you travel."

She said: "Looking forward, everyone says, 'Well how are we going to get out of this?'

"I think if these vaccines stop transmission, which they look like they might, we will reach a stage of vaccine passports.

"It's already being discussed in the EU. 

HeraldScotland:

"We already have countries like Israel [which] have introduced green cards domestically if you actually have gotten vaccinated. 

"And I think similar to yellow fever, where the WHO [World Health Organisation] has certification if you've been vaccinated, we'll reach a state where aviation will continue – and Spain and Greece are really keen on this for their tourism industries – where you will be allowed to fly and we can have international mobility, but only when people are vaccinated and we have that confirmation that you will not infect others when you travel."

Ms Sridhar later added: "So it's heading this way... Scotland needs to be ahead of this and preparing for it, and thinking actually if we're going to do it, how do we do it properly."

What "vaccine passports" are out there?

The European “Digital Green Pass” is the most recent concept to emerge, but is by no means the first.

The Travel Pass initiative from the International Air Transport Association is another app-based system.

CommonPass is a collaboration between Swiss not-for-profit tech organisation The Commons Project and the World Economic Forum, among others.

Meanwhile, AOKpass consolidates medical records into a form where they can be checked by authorities.

Elsewhere, VeriFLY also promises "a faster return to safe, in-person experiences" and is being trialled by British Airways on selected routes.

Are there any concerns?

The use of coronavirus “vaccine passports” to help businesses reopen post-lockdown could put venues at risk from possible claims for discrimination.

Phil Clapp, chief executive of the UK Cinema Association (UKCA), said that requiring proof of receipt of a Covid-19 jab presented “a range of practical and legal problems”.

His comments came after the Prime Minister suggested that rapid testing will be used over vaccine passports to support businesses re-opening once lockdown restrictions ease.

Meanwhile, charities including the Ada Lovelace Institute have also raised concerns about data privacy and the potential for discrimination.

For instance, if employers favour candidates that have had the vaccine, while certain people cannot get the vaccine for health reasons.