Ministers are considering tighter restrictions on smoking outdoors as part of a drive to phase out tobacco.
As first reported by the Sun, smoking could be banned in pub gardens, outdoor restaurants, outside hospitals and sports grounds.
The measures are being proposed as part of a toughened-up version of the last government's Tobacco and Vapes Bill, which would outlaw the sale of tobacco to anyone born on or after January 2009.
That Bill was introduced in Parliament but fell once the general election was called.
The King's Speech at the state opening of Parliament last month promised to reintroduce the legislation to increase progressively the age at which people can buy cigarettes.
The Sun said secret Whitehall papers confirmed the plan to extend the indoor smoking ban despite some opposition within government.
The Department of Health and Social Care said it did not comment on leaks but was considering a range of measures to "finally make Britain smoke-free".
A spokesperson said: "We do not comment on leaks. Smoking claims 80,000 lives a year, puts huge pressure on our NHS, and costs taxpayers billions.
“We are determined to protect children and non-smokers from the harms of second-hand smoking.
"We’re considering a range of measures to finally make Britain smoke-free.”
Discussing the Sun's front page story on BBC Newsnight, Lord Stewart Wood, a former adviser to Labour's Gordon Brown, told the programme: "There's a difference between smoking outside and walking in a forest and smoking outside where there are large groups of people, particularly children, concentrated, like restaurants, like pub gardens, like football matches."
But former Conservative special adviser Anita Boateng told the BBC: "It feels a very draconian step for people who are adults who can make decisions and who can legally smoke.
"The point is you are in an outside area of a pub garden in a walled off area. You don't have to stand there if you don't want to experience second-hand smoking."