(Bloomberg) -- Boris Johnson risks a boycott of his own Conservative Party conference if he goes ahead with plans to force large venues in England to demand so-called vaccine passports on entry.

Tory members of Parliament and party members attending the conference in Manchester, northern England in October will need to prove they’ve been fully vaccinated against Covid-19 if government rules are in place by that point, a person familiar with the matter said.

That could see a significant proportion of the party refuse to attend, potentially overshadowing Johnson’s attempt to focus attention away from his handling of the coronavirus pandemic and onto his “leveling up” agenda.

Lockdown-skeptic Conservative MPs have expressed dismay over Johnson’s plan to mandate vaccine passes for nightclubs and other large, crowded venues in England from September, after all adults have been offered shots.

Covid Passports Plan for U.K. Nightclubs Sparks Business Ire

The plan requires Johnson to secure Parliament backing via a vote, with defeat a real possibility because Labour has indicated it could oppose the plan. But even if so-called Covid passes do not become law, government guidance may still mean they’ll be used at the Conservative conference.

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