Smoking in cars carrying children will be banned after MPs voted overwhelmingly to approve the plan in a Commons vote.

Tory and Liberal Democrat MPs, who were given a free vote, joined forces with Labour MPs to approve the ban by 376 votes to 107, majority 269.

Tonight's vote comes after peers amended the Children and Families Bill to give the health secretary the power to impose a ban.

Despite opposition from some Tories, including Cabinet members, MPs decided to uphold the change to the legislation made by peers last month.

Earlier, Health Minister Jane Ellison told MPs the success of a smoking ban in cars carrying children will not be measured by the number of times the police enforce it.

Instead, she said, its success would be gauged by the reduction in exposure to second-hand smoke.

She told the Commons: 'The Government has sought to reflect the views expressed by those in the Lords by bringing forward an amendment that is technically workable.

'And there is going to be debate on it and we will see what the view of the house is and we will take our steer on the principle of the issue then having heard the views of both houses.

'In the event that legislation is to be brought in to stop smoking in cars carrying children, we should not measure success by the number of enforcement actions.

'We should measure success by the reduction in exposure to second-hand smoke.

'The Government will listen very carefully to what Parliament has to say on the important principle as to whether the Government should have the power to legislate to prevent smoking in cars when children are present.

'We will then consider what needs to happen next which is why, if MPs will forgive me, I am not able to talk in great detail on some of the points you have asked me about because that is the next stage once we have heard the will of Parliament expressed.

'However, whatever happens I have asked Public Health England to continue their work on behaviour change in this area, including through social marketing campaigns.'

MPs are considering Lords amendments to the Children and Families Bill.

One change would give ministers the power to introduce standardised packaging for cigarettes but implementing plain packs would be subject to a review and a ministerial decision.

Other amendments put forward by peers would prohibit the sale of electronic cigarettes to under-18s and ban proxy buying - when adults buy tobacco for under age children.

The original amendment banning smoking in cars carrying children was tabled by Labour.

Its shadow health minister in the Commons Luciana Berger said it had to go ahead. She said: 'This is a matter of child protection not adult choice.'

But several Conservative MPs were unhappy at the proposals.

Philip Davies (Shipley) said passing the amendment would be 'yet another in a long line of triumphs for the nanny state'.

He said: 'If we want to encourage a system in this country where parents take responsibility for their children we have to give them responsibility for their children.'

Former children and families minister Tim Loughton said Labour would 'criminalise pregnant women who smoke, on the basis that their child is in an even more confined space than in a car'.

Norwich North MP Chloe Smith, who abstained, said: 'I abstained because, after listening to many points throughout the debate, I still found good arguments on both sides. I believe in law that is necessary and enforceable at sensible cost to the taxpayer; and it was hard to support this proposal because it could carry some very odd consequences. For example, it could have criminalised a 19 year old smoking in a car with a 17 year old - who is already legally allowed to smoke in their own right. But it was hard to oppose the proposal too because I voted during the same session in favour of other measures to reduce smoking. With equal arguments for and against I thought it was most sensible to abstain. I also heard from few constituents but even that small number of views fell on both sides.'