image copyrightGetty Images
The government is considering whether vaccine passports could be used at big events in future, the BBC understands.
A review of the use of the certificates in England is expected to confirm on Monday they will not be compulsory.
No formal decision has yet been made but a Whitehall source said they could have a role to play at large events, such as sports matches and concerts.
It is thought they could also help to prevent business closures if there was a wave of the pandemic this winter.
A committee of MPs has warned ministers against introducing the certificates, saying they would be unjustified and discriminatory.
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'Passports not the answer'
People travelling abroad can show they have been vaccinated using the NHS app in England or, in Scotland and Wales, a certificate.
There have been suggestions that a similar system showing proof of vaccination or a negative Covid test could be set up domestically to enable parts of the economy to reopen more fully.
But the idea has been controversial, with the UK's equality watchdog warning that it could create a "two-tier society".
The UK government has been conducting a review for England which is due to report back ahead of Monday's announcement on the roadmap out of restrictions.
image copyrightGetty Imagesimage captionImmunisation record cards like this could be supplemented with certificates acting as passports to certain events
However, the Commons Public Administration and Constitutional Affairs Committee called for the certification to be scrapped, saying it should not be a part of the planned rolling back of restrictions on 21 June.
The implementation would "by its very nature be discriminatory", MPs said, and there was no justification for their use "sufficient to counter what is likely to be a significant infringement of individual rights".
The report also said "conflicting and sometimes contradictory statements" by ministers on the possibility of introducing certificates "risked damaging trust in government and in the measures put in place to tackle the pandemic".
Committee chairman William Wragg said: "We recognise the need to formulate an effective lockdown exit, but Covid passports are not the answer.
"We are entirely unconvinced by the case for their introduction.
"Although it is a tool that is being sold as and built with the intention of being for the universal good, it has the potential to cause great damage socially and economically.
"As vaccine uptake statistics indicate, any Covid certification system will be a discriminator along the lines of race, religion and age."
Cabinet office minister Michael Gove, who is leading the review, previously said the benefits of a vaccine passports scheme were "finely balanced".
He has visited Israel as part of the process to assess the effectiveness of a similar "green pass" scheme deployed in the Middle East country.
But he said that if such a scheme proved too costly or too much "hassle" for the hospitality industry, then the UK government would not pursue it.
The NHS app has already been altered to allow users to prove their vaccine status and Mr Gove said further changes were in the pipeline so test results could be declared as well.
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It comes as the government considers delaying the lifting of England's remaining Covid restrictions by up to four weeks.
There is growing concern over rapidly increasing cases and the higher transmissibility of the Delta variant.
On Friday, another 8,125 virus cases were recorded in the UK, according to official figures, and another 17 people died within 28 days of a positive test.
With additional reporting by Alex Therrien