MPs have voted overwhelmingly in favour of a motion that is the first step towards criminalising smoking in cars in the presence of children.
The measure - which was passed in the House of Lords last month - was approved in a free vote in the House of Commons by 376 votes to 107, a sizable majority of 269. It grants the government powers to implement a ban on smoking in cars carrying underage passengers.
The 'no' camp included Justice Secretary Chris Grayling and Home Secretary Theresa May, who criticised the plan as unworkable and an infringement of personal liberty.
Deputy PM Nick Clegg also voted no, citing his belief that the proposed ban would "sub-contract responsible parenting to the state."
The Prime Minister, David Cameron, was not in attendance for the vote, as he was in the south-west visiting communities devastated by recent floods. However, he voiced his support for the measure through a spokesman, who said the Prime Minister believed that "the time for this kind of approach has come."
It was one of a raft of measures related to tobacco laws that came up in last night's session as part of a Labour amendment to the Children and Families Bill. MPs also voted to ban the sale of e-cigarettes to minors and to criminalise 'proxy buying' of cigarettes by adults for underage people.
A majority of Commons members also approved a measure to give the Government power to introduce plain packaging on tobacco products. Campaigners for plain packaging have already been successful in Australia, with similar laws under consideration in several other Commonwealth countries.
Seven hundred health experts had written to Parliament urging members to vote in favour of the measure, and this morning anti-smoking and child safety campaigners had cause for celebration.
Dr Penny Woods of the British Lung Foundation said in a statement that "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."
However, Whitehall insiders warned that it may be some time yet before the proposed ban comes into effect.
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