THEY were once branded “discriminatory, unnecessary and intrusive” by UK ministers but now Boris Johnson is, or rather appears, intent on making them mandatory: vaccine passports.

It was just three weeks ago Whitehall published its review into whether the so-called digital NHS Covid Pass, in use for foreign travel, should be introduced in a domestic setting south of the border.

The review said no, concluding: “The impacts are judged to be disproportionate to the public health benefit at this stage of the pandemic.”

Wisely, the UK Government covered its back, saying it would keep things under review. The start of the U-turn took barely a week.

On July 12, Sajid Javid, England’s new Health Secretary, announced businesses and large events would be “encouraged” but not required to use the Covid Pass - which shows if someone has been vaccinated and/or recently tested - in “high risk settings to help limit the risk of infection”.

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But it also warned: “If sufficient measures are not taken to limit infection, the Government will consider mandating the NHS Covid Pass in certain venues at a later date.”

On July 19, so-called Freedom Day, the Prime Minister completed the U-turn. To the surprise of many, he told a Downing St press conference the Covid Pass would be brought in for nightclubs and other large indoor venues; but not until the end of September.

The key detail is adults going to a nightclub will have to be double-jagged to gain entry; proof of a negative test will no longer suffice.

The move is partially aimed at getting young people immunised; more than a third have not yet been vaccinated.

During PMQs, Keir Starmer asked why on earth had Boris announced the Covid Pass plan would become operational from September.

The PM was disdainful, saying it was “blindingly obvious to everybody” why; it was “common sense” to do it this way because by then young people would have had the chance to get two inoculations.

Sir Patrick Vallance, the UK Government’s Chief Scientific Advisor, explained the Covid Pass in nightclubs and other venues where people were crowded indoors was needed because they were a “focus for potential super-spreading events”.

Which bodes the blindingly obvious question: why open up nightclubs for 10 weeks when people, many of whom will be unvaccinated, can spread the virus? It seems completely illogical.

As Sir Patrick also pointed out when nightclubs opened up in Holland and Israel “you saw a big increase in cases”. Both countries have now closed them again.

Understandably, the hospitality sector was not happy, denouncing the move as an “absolute shambles”. It came on the day nightclubs were allowed to open for the first time in 16 months.

But where will the requirement for a Covid Pass end? How will the policy be policed?

Mr Johnson insisted he did not want to see “passports for pubs” but conspicuously did not rule out their introduction. Some of the successful trials on using Covid certification include football matches.

Indeed, the PM ominously noted: “Some of life’s most important pleasures and opportunities are likely to be increasingly dependent on vaccination.”

Yesterday when asked how long the list would be and if it could include the political parties’ autumn conferences, Kwasi Kwarteng, the Business Secretary, said it would contain a “limited range of indoor events; there will be more clarity on that later”. Some Tory MPs have threatened to boycott the party event if Covid Passes become mandatory.

In a Commons statement, Nadhim Zahawi, the Vaccines Minister, said that the vaccine passport plan would not apply to schools, universities or indeed “any public buildings,” including the UK Parliament.

Some countries have introduced or are planning to introduce a form of Covid Pass for domestic venues amid growing controversy.

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Nowhere more so than in France, where there have been large demonstrations against President Emmanuel Macron’s plan to extend its use to cafes, bars, restaurants and theatres as well as trains and coaches. It comes as infection rates have seen a “stratospheric” rise; 150% in just a week.

Meanwhile, Nicola Sturgeon has kept her options open as she considers the reopening of nightclubs in Scotland, set for August 9.  

The First Minister explained how Covid passports raised “sensitive ethical and equity considerations” and they would be “carefully considered…over the next period”.

Yet the prospect of the SNP helping to inflict a Commons defeat on Boris may be too tempting to forego.

While Mr Kwarteng yesterday insisted that the Government was “absolutely committed” to introducing Covid Passes for certain venues and Mr Zahawi confirmed to MPs “at the end of September we plan to make full vaccination a condition of entry to those high risk settings where large crowds gather and interact,” they seemed more convinced than their boss. After having announced the passport plan on Monday, the PM later said ministers were only “considering” it.

Perhaps the reason for the subtle shift was the little matter of getting it through Parliament.

Labour is opposing the scheme, saying it is “costly, open to fraud and is impractical”. Some 42 Conservative MPs have signed a petition against Covid certification being used for “general services, businesses or jobs”. Tory WhatsApp groups have been flooded with complaints about compulsory vaccine passports.

Given the Government has a majority of 80, the numbers don’t look good for Boris. Mr Kwarteng observed: “If the vote does occur, I’m confident the Government will preserve a majority.” Note the word ‘if’.

Should the PM feel that he does not have the Commons numbers, he will pull the measure to avoid a humiliating defeat. It would be another embarrassing U-turn to add to the list. By now, of course, we’re getting used to them.