Police could soon be stopping motorists seen smoking with children on board after MPs approved the policy by a majority of 269.
Smoking in cars when children are present could soon be illegal after MPs voted overwhelmingly in favour of the policy.
Coalition MPs, who were given a free vote, joined forces with Labour to approve the ban by 376 votes to 107 – a majority of 269.
David Cameron missed the vote while visiting flooded areas in the south west, but the Prime Minister is thought to support the proposed law.
His official spokesman told a regular Westminster media briefing: “While he understands the concerns that some have expressed, his view is that the time for this kind of approach has come.”
Justice Secretary Chris Grayling was one Cabinet minister in the no camp, believing any law would be unenforceable.
Monday night’s vote came after peers amended the Children and Families Bill to give health secretary Jeremy Hunt authority to impose a ban.
Medical charities are “delighted” with the result.
Dr Penny Woods, chief executive of the British Lung Foundation, said: “Having campaigned on this issue for many years, we’re absolutely delighted that MPs have backed the ban on smoking in cars carrying children.”
“This could prove a great leap forward for the health of our nation’s children.”
“The introduction of a law that would help prevent hundreds of thousands of children from being exposed to second-hand smoke in the car is now within reach.”
“With both Houses of Parliament having made their support for the ban clear, the onus is now on the Government to act accordingly and make this crucial child protection measure law at the earliest opportunity.”