MPs should be recalled to debate the "threat" of domestic vaccine passports, backbench Tories have argued.

       Andrew Bridgen, one of 43 Conservative MPs to sign a declaration opposing vaccine passports, said Parliament should be recalled from its summer recess if ministers are "serious" about asking people to show proof of their vaccine status to gain entry to domestic venues and events.

       The call means cross-party backing is emerging for the Commons to return before September.

       Last week, the Liberal Democrats said a change rolled out to the NHS app, allowing users to prove they had been double-jabbed to access domestic settings - as well as for international travel - warranted a recall.

       Sir David Lidington, a Conservative grandee, added his voice to the growing number of Tory MPs who are concerned about the prospect of vaccine passports, which are being used in some European countries, including Denmark and France.

       The former cabinet minister told Times Radio on Sunday that introducing a "government certificate of approval" to access certain events would set a "dangerous precedent".

       Boris Johnson has announced that he intends to change the rules in September so that only those who are fully vaccinated can attend nightclubs, in a move designed to increase the take-up of vaccination among young people.

       The nightclub stipulations would be stricter than the coronavirus status certificates used at some mass events in recent months, with clubbers not allowed to use proof of a negative Covid-19 test or evidence of having had the virus to gain entry.

       But the Prime Minister was warned by one of his backbenchers that he faced an "embarrassing defeat" if he were to put the "authoritarian" proposal to a vote in the Commons.

       Mr Bridgen, the North West Leicestershire MP, told LBC radio: "I think if the Government is serious about the threat of bringing in domestic vaccine passports then, of course, Parliament should be recalled.

       "This is a very serious infringement on people's liberties, it is basically unprecedented in this country, and I and a number of colleagues would oppose it."

       Labour's shadow environment secretary, Luke Pollard, said the party was "very cautious" about domestic Covid passports, with the party leader Sir Keir Starmer ruling out supporting them for use in "everyday life", setting up the possibility of a government defeat on the policy.