British lawmakers will debate and vote on the government’s plans to introduce a landmark smoking ban on Tuesday. The bill, a key policy announced by Conservative Prime Minister Rishi Sunak last year, will make it illegal to sell tobacco products to anyone born after January 1, 2009. It has the support of the opposition Labour Party and is expected to pass. But Sunak faces rebellion from more libertarian-minded members of his party, who criticized the proposals as “unconservative.” Authorities say that if passed, the bill will create Britain’s “first smoke-free generation.” Under the Tobacco and Vapes Bill, children turning 15 this year or younger will never be legally sold tobacco. The legal age of sale that people can buy cigarettes will be raised by one year, every year until it is eventually illegal for the whole population. The bill also includes measures to crack down on youth vaping, such as banning and limiting their flavors to prevent children from becoming addicted to nicotine. It is currently illegal for anyone to sell cigarettes or tobacco products and vapes to people under 18 years old throughout the U.K. Opponents, such as the smokers’ rights lobbying group FOREST, said the move will fuel the black market and “treat future generations of adults like kids.” Last week former Prime Minister Boris Johnson called the plans “absolutely nuts.” Despite some opposition, the bill is expected to comfortably clear its first hurdle in the House of Commons when lawmakers vote on it later Tuesday. The plans were believed to have been inspired by similar policies proposed by New Zealand under former Prime Minister Jacinda Ardern, but the country’s new coalition government repealed the bill earlier this year.