A source close to Suella Braverman, who was sacked as home secretary by Mr Sunak in November, told The Telegraph she was “not a fan” of the proposals.
It is understood that Liz Truss, the former prime minister, will vote against the ban on Tuesday, and that she hopes to catch the eye of Sir Lindsay Hoyle, the Commons Speaker, to make a speech criticising her successor’s flagship policy.
Ms Truss has called the proposals “profoundly unconservative” and an example of the “nanny state” in action, prompting Mr Sunak to respond that there was “[nothing] unconservative about caring for our children’s health”.
Meanwhile, Boris Johnson called Mr Sunak’s plan “absolutely nuts” as he criticised the wider state of the Conservative Party at an event in Canada.
Speaking at a gathering of conservatives in Ottawa on Wednesday, the former prime minister said: “We are, on the whole, in favour of freedom, and it is that single Anglo-Saxon idea of freedom that I think unites conservatives, or should unite conservatives.
“And when I look at some of the things that we are doing now, or that are being done in the name of conservatism, I think they are absolutely nuts. When the party of Winston Churchill wants to ban cigars, donnez-moi un break, as they say in Quebec. It’s just mad.”
Although dozens of Tory MPs are understood to have concerns about the smoking ban, rebels are split about whether to oppose the Bill outright or attempt to amend it. There will not be the opportunity for changes until it moves to its report stage following Tuesday’s vote.
Emily Foster is a globe-trotting journalist based in the UK. Her articles offer readers a global perspective on international events, exploring complex geopolitical issues and providing a nuanced view of the world’s most pressing challenges.