Rishi Sunak is facing the prospect of another backbench Tory rebellion as he puts forward controversial plans to stop young people from ever smoking.

The plan, being presented before the Commons for the first time today, would make it illegal to sell tobacco products to anyone born after January 1, 2009.

The bill would raise the smoking age every year, so that those born after 2009 would never be able to legally purchase tobacco products.

Opponents of the ban include Mr Sunak’s immediate predecessor, Liz Truss, who has previously described the plans as “profoundly unconservative”.

Former prime minister Boris Johnson also described the plans last week as “nuts”.

Conservative MPs have been granted a free vote on the legislation, and several are expected to oppose the Tobacco and Vapes Bill when it has its first full debate in the Commons on Tuesday.

But Labour has given its backing to the proposals, making it likely that the legislation will clear this first hurdle regardless of any Conservative opposition.

Ahead of the debate, doctors and health charities urged MPs to vote in favour of the proposals, which would ensure that nobody aged 15 or under today would ever be able to legally buy tobacco products.

Professor Steve Turner, president of the Royal College for Paediatrics and Child Health, said the Bill would “without a doubt … save lives”.

He said: “By stopping children and young people from becoming addicted to nicotine and tobacco, we decrease their chances of developing preventable diseases later in life, and will protect children from the harms of nicotine addiction.

“As paediatricians, we strongly urge MPs to use the important responsibility they have and support this Bill to protect children’s and our nation’s current and future health.”

Charmaine Griffiths, chief executive of the British Heart Foundation, said: “Decisive action is needed to end this ongoing public health tragedy – we urge every MP to vote for this landmark legislation at the Bill’s second reading.”

As well as raising the smoking age every year, the legislation includes provisions that will regulate the display, contents, flavours and packaging of vapes and nicotine products.

Smoking kills about 80,000 people a year and costs the NHS and the economy an estimated £17 billion annually.

According to the Government, creating a “smokefree generation” could prevent more than 470,000 cases of heart disease, stroke, lung cancer and other diseases by the end of the century.