The coronavirus vaccine passport app crashed moments after Boris Johnson announced ‘Plan B’ measures.
From next week, the NHS Covid pass will be mandatory for entry into nightclubs and venues with larger crowds.
It froze after numerous people tried to access the app.
The digital passport can be used as proof of your vaccination status which can be kept on your smartphone.
Boris Johnson said the pass can be obtained by anyone with two doses of the vaccine.
He said: “We will also make the NHS Covid pass mandatory for entry into nightclubs and venues where large crowds gather, including unseated indoor venues with more than 500 people, unseated outdoor venues with more than 4,000 people and any venue with more than 10,000 people.
“The NHS Covid pass can still be obtained with two doses but we will keep this under review as the boosters roll out.
“And having taken clinical advice since the emergence of Omicron, a negative lateral flow test will also be sufficient.
“As we set out in Plan B, we will give businesses a week’s notice, so this will come into force in a week’s time, helping to keep these events and venues open at full capacity while giving everyone who attends them confidence that those around them have done the responsible thing to minimise risk to others.”
The Prime Minister announced the new measures as the omicron variant has been “spreading incredibly fast” with its rate doubling every 2 to 3 days.
He told a Downing Street press conference: “It has become increasingly clear that Omicron is growing much faster than the previous Delta variant and is spreading rapidly all around the world.”
While 568 cases had been confirmed in the UK “the true number is certain to be much higher”.
“Most worryingly, there is evidence that the doubling time of Omicron could currently be between two and three days.”
Boris Johnson told a Downing Street press conference: “We can’t yet assume that Omicron is less severe than previous variants.
“So while the picture may get better, and I sincerely hope that it will, we know that the remorseless logic of exponential growth could lead to a big rise in hospitalisations and therefore, sadly, in deaths.
“That’s why it is now the proportionate and the responsible thing to move to Plan B in England while continuing to work closely with our colleagues in the devolved administrations, so we slow the spread of the virus, buy ourselves the time to get yet more boosters into arms, especially in the older and more vulnerable people.”
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Among other restrictions is new guidance to work from home.
He said: “We will reintroduce the guidance to work from home.
“Employers should use the rest of the week to discuss working arrangements with their employees but from Monday you should work from home if you can.
“Go to work if you must but work from home if you can.
“I know this will be hard for many people but by reducing your contacts in the workplace, you will help slow transmission.”
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