The Cabinet minister confirmed that people in England who travel abroad will be able to use the NHS app to demonstrate they are fully vaccinated when the ban on overseas leisure travel is lifted on Monday.
The app is currently used to book medical appointments and order repeat prescriptions, and is different from the Covid-19 app.
People who do not have access to a smartphone and know the country they are travelling to requires proof of vaccination status can call the NHS helpline 119 from Monday and ask for a letter to be posted to them.
Mr Hancock told Sky News: “The certification, being able to show that you’ve had a jab, is going to be necessary for people to be able to travel.
“So, we want to make sure people can get access to that proof, not least to show governments of other countries that you’ve had the jab if they require that in order to arrive.
“Israel’s a good example. They’ve said that they’ll want proof of you having had two jabs for you to go to Israel as and when they open up. They’re on the green list of course.
“So we will make sure that you can get access to that, to prove that point.”
Mr Hancock said the use of so-called vaccine passports is “different to the question of whether we require people to be certified as Covid-secure before doing things domestically”.
He added: “The focus for the time being on this certification question, is making sure that people can travel internationally and show that they’ve had the jab if that’s what another country requires.”
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