British Prime Minister Rishi Sunak is set to ban the sale of disposable vapes to prevent their use by children and reiterate the government's intention to introduce a law preventing younger generations from buying tobacco.

Under the new powers, there would be restrictions on vape flavours, a requirement for plain packaging, and changes to how vapes, or e-cigarettes, are displayed to make them less attractive to children.

"Alongside our commitment to stop children who turn 15 this year or younger from ever legally being sold cigarettes, these changes will leave a lasting legacy by protecting our children's health for the long term," Sunak said in a statement.

Smoking is Britain's biggest preventable killer, causing one out of four cancer-related deaths, or some 80,000 a year, the government says.

In October, Sunak announced plans to pass a law which would mean that anyone born on or after January 1, 2009, would be unable to buy tobacco in their lifetime.

While vapes are considered key to helping people quit smoking, there has been concern they could be driving nicotine addiction among young people, with nine per cent of 11 to 15-year-olds now using them, the government said.

The World Health Organisation (WHO) said in December all vape flavours should be banned.

However, industry groups and the UK Vaping Industry Association argue that vapes pose significantly lower health risks than tobacco, and flavours were key in encouraging smokers to switch.

"I have an obligation to do what I think is the right thing for our country in the long term," Sunak said.

"That is why I am taking bold action to ban disposable vapes - which have driven the rise in youth vaping - and bring forward new powers to restrict vape flavours, introduce plain packaging and change how vapes are displayed in shops."

The government says that along with the health benefits, the ban on disposable vapes would help the environment, with five million thrown away each week.