Smoking should be banned in cars carrying children, Health Minister Anna Soubry said.
Ms Soubry said the Government should "consider" the move to protect children, BBC News reported.
David Cameron has previously said, while he supports the smoking ban in public places, he is "more nervous" about legislating what people do inside a private vehicle.
Giving her personal view on the subject at the Local Government Association's annual public health conference, Ms Soubry said: "I would ban smoking in cars where children are present.
"I would do that for the protection of children. I believe in protecting children. I would see it as a child welfare issue.
"I think it is something we should at least consider as government."
While ministers are not considering a ban, the Department of Health has run marketing campaigns encouraging people not to smoke in the presence of their children at home or in cars.
Later Ms Soubry said: "I expressed my own views on smoking in cars and the health threat it causes to children. We have no current plans to change government policy.
"It remains the case that smoking is one of the biggest challenges in public health and as such it requires a range of responses, including encouraging people to change their behaviour - which is why we will soon repeat a national marketing campaign to remind smokers of the risks of exposing children and adults to second hand smoke."
Exposure to second-hand smoke is linked to several children's health problems, including sudden infant death, meningitis and respiratory conditions such as asthma and wheezing. Recent research from the University of Aberdeen found that smoking in cars produces pollutants which could be harmful to passengers.