Labour is seeking to impose a ban on smoking in cars while children are present.
Shadow public health minister Luciana Berger said the party intends to force a vote on an amendment to the Children and Families Bill in the House of Lords which it is tabling later today.
If it succeeds in getting the measure on to the statute book, it would make it an offence for drivers of private vehicles to fail to prevent smoking when a child is present.
Berger said that almost 500,000 children in England were exposed to potentially toxic levels of second-hand smoke in family cars every week.
"We know that children are particularly vulnerable to passive smoking. We know that a single cigarette can create concentrations of tobacco smoke in a car that is 23 times more toxic than in a typical house," she told BBC Radio 4's Today programme.
"Ministers have scrapped research that the last Labour government commissioned on smoking in cars with children. They have tried to kick this issue into the long grass and that's why Labour has brought forward these proposals today and why we are going to force the vote in Parliament."
Simon Clark, of the pro-smoking lobby group Forest, said legislation would be difficult to enforce and he accused Labour of "playing politics" with the issue.
"We think legislation is a very heavy-handed way to tackle this problem. I don't think it is as big a problem as they like to make out. The vast majority of smokers wouldn't dream of lighting a cigarette in a car with a child," he said.
"We don't need legislation that would be very, very difficult to enforce.
"Our concern is that what would happen is people will then say 'Let's have a ban on smoking in all private vehicles' so you could have a lone driver on his own in his own vehicle lighting a cigarette and he would be committing an offence.
"If you say 'Let's ban smoking in cars with children present', are you going to go on and try and ban smoking in the home if children are present?
"I think this would set a very bad precedent and lead to a lot of problems."Suggest a correction