A ban on the sale and supply of single-use vapes comes into effect in Northern Ireland today.
It means that for a time at least there will be different approaches on both sides of the border.
The Irish Government is drafting equivalent legislation, but it is not ready yet. Notification to the EU will also delay implementation for a number of months.
The Irish Heart Foundation has said while the situation persists children in the north are being better protected than those in the south and wants the Government to fast-track the law.
The cabinet agreed to implement a ban last year, but work was interrupted when the Dáil was dissolved for the election.
The new law in Northern Ireland makes it a criminal offence to sell or supply single-use vapes with a maximum penalty of up to two years in jail and a fine.
Businesses have been given six months to prepare for the change by selling existing stock.
Similar laws are being enacted by devolved administrations in England, Wales and Scotland today too, effectively making it a UK-wide ban.
It is estimated that five million disposable vapes are thrown away in the UK every week.
Stormont Environment Minister Andrew Muir said it was a "milestone day".
He said the Executive had been prompted to act by the environmental and health risks posed by single-use vapes.
Many are littered by users, and the product has proven popular with young teenagers who sometimes progress to tobacco products.
Paper stickers, which users must remove to activate the vape are routinely stuck on litter bins creating an unsightly mess.
There have also been concerns that the multitude of flavours and the branding is marketing the products at children.
"The environmental consequences around this are significant. We're also very aware that in terms of disposable vapes they can be much more attractive for younger people, and we want to be able to tackle that," Minister Muir said.
Research in Northern Ireland shows that one in five of 11–16-year-olds have tried vapes, even though the legal age for purchase is 18.
The Irish Heart Foundation said it had taken a considerable period to get age restrictions for vapes over the line in the Republic and it now wanted to make sure there was rapid progress.
Director of advocacy with the Irish Heart Foundation Chris Macey said: "We’re sort of lagging a bit behind. I suppose our concerns is that it took years to get the ban on the sale of vapes to U-18s over the line and we just want to make sure there’s no undue delay on this occasion because as long as there is children in this part of the country won’t be as well protected as children in the north."
Mr Macey added: "Disposable vapes have been a big contributor to the explosion of youth vaping in Ireland and everything that goes with that, the nicotine addiction that is seen by research to be a likely gateway into smoking, which is still killing 12 people a day in Ireland."
Mr Macey said research showed that children who vape are three to five times more likely to end up smoking, and statistics showed that around a third of 15-16-year-olds in the Republic have vaped.
