The first minister of Wales insists "fewer lives will be lost" on Welsh roads - as the new national speed limit of 20mph is introduced across the country.
Nearly all roads in built-up or residential areas in Wales have now become, by default, 20mph instead of 30mph.
The plan is hugely controversial - with the leader of the House of Commons Penny Mordaunt describing it this week as "absolutely insane, even by the standards of the Labour Welsh government."
But Mark Drakeford told Sky News the new law is about safety, not politics.
"It's not a political item in any sense, it is grounded in the evidence," he said.
"The key positive is reduced speed means fewer accidents, and fewer lives being lost. The evidence I think is incontrovertible, that lower speed limits reduce accidents, reduce damage done to people.
"I have no doubt that the Tories will try to weaponise this sort of thing, it's just in their nature. I am very confident people in Wales will see through that."
The Welsh government hopes the new law, which has cost £32m to introduce, will see 40% fewer collisions, save six to 10 lives a year and up to 2,000 avoiding injury.
Mr Drakeford said the results from Spain demonstrate the benefits.
"In 2019, Spain introduced a law very similar to what we have in Wales," he said.
"They've had a 20% reduction in urban deaths that have followed, 34% reduction in cyclist fatalities."
The rollout comes after two years of trials in eight areas of Wales, including in the Heath, north Cardiff.
Parents attending a baby group at the local community centre have mixed feelings over whether it has worked.
"I think there's no doubt that people are safer if cars are driving slower and injuries are less severe is an accident, so I think it's a positive thing," one mother told Sky News.
Road rage risk
Richie, one of the fathers at the group, doesn't feel the new limit has worked.
"I think there's been a huge amount of road rage with it," he said. "I was overtaken yesterday doing 20mph, a guy was doing 40mph, I don't agree with it at all - it's a horrendous idea."
Melanie, another mother, doesn't think a blanket roll-out is the right approach.
She said: "I don't know if people really abide to it. I often see people flouting 20mph, particularly around the park. I think it makes sense, particularly around schools and parks…the whole of Cardiff? I don't think so."
There are numerous campaign groups against it, mainly focusing on the impact in their local area.
Stephen Clark is a member of the group "20mph Limit - Democracy for Wales" in Heath. He admits 20mph is safer, but only in the places that it is required.
"It is not necessary in the main arteries that run through the city where people travel daily, to and from work. I just feel it's very unfair on the general public," he says.
"I believe it leads to more erratic driving. It's very difficult to adjust to this new 20mph speed limit because you're constantly having to monitor your speed."
An online petition against the scheme has secured more than 70,000 signatures. There are economic concerns too.
The Welsh government's own report has found that over a 30-year period the economic impact of the slower speed limit could be in the region of £4.5bn. It is keen to focus on the £92m annual saving to the NHS.
Welsh Conservative shadow transport minister Natasha Asghar MS urged the Labour government to scrap the "vanity project", saying the 20mph policy will "slow emergency services down, cost the economy up to £9bn, and impact people's livelihoods".
The new speed limit will be enforced by police as normal, but the first minister told Sky News there will be an educational approach to the public in the first instance.
"We are very committed, alongside the police colleagues, to an approach that is about education, informing, giving people time to ensure they understand the law has changed, nobody is going to be rushing in with a heavy hand," Mr Drakeford said.
"There will come a point where people who are persistently refusing to do the things that everybody else is doing, then they won't be able to do that with impunity."