Adults who are caught smoking in cars in which children are passengers will face fines of 100 euro.

The regulations giving effect to the law will be outlined by the Health Minister Leo Varadkar and Children's Minister James Reilly today.

The offence is expected to take effect in two weeks and will be policed by Gardai.

It carries a fine of 100 euro and if it's not paid, the case can be brought to court with hefty penalties applied.