The Health Minister is expected to announce January first as the day that it will no longer be legal to smoke in a car with children.
The laws were passed by the Oireachtas a year ago but Gardaí were given time to work out how they would be enforced.
A formal announcement is to be made by Leo Varadkar and Children's Minister James Reilly later this morning.
It's expected that the offence will carry a fine of €100.
New Year's Day is likely to be the first time the new laws will come into effect.
Several studies have highlighted the dangers to children who inhale second hand smoke.