WALES' new 20mph speed limit "will have an impact" on how long it takes emergency services to respond to 999 calls, a top cop has said.

In an email obtained by the Welsh Conservatives through a Freedom of Information request a senior South Wales Police officer said the new limit "will have an influence on how fast police travel and may impact how they respond".

The message was sent from South Wales Police Assistant Chief Constable Mark Travis to all fire, police and ambulance services in Wales.

However, ACC Travis has since said he believes response times will not be affected - and the roads being slower will in fact make it easier for emergency services to make progress.

In an interview with BBC Radio Wales this morning ACC Travis said the new speed limit ‘is quite a large change.’

“We already have 20mph limits within Wales which we already observe and respond to," he said. "Whilst this is new in terms of the scale, this is not new in terms of ways of working.

“It is quite a large change that will have a big impact on society.

"Actually, sometimes the road being slower makes it easier for emergency service vehicles to make progress. It's easier to pass a slower vehicle than a faster vehicle."

South Wales Argus: New 20mph signs installed in Abergavenny during a speed limit trial schemeNew 20mph signs installed in Abergavenny during a speed limit trial scheme (Image: Newsquest)

The new speed limit comes into force on September 17 and all roads in Wales that are currently 30mph will be dropped to 20mph by default with some exceptions.

ACC Travis said around 20 per cent of South Wales Police  officers - including traffic officers, armed officers, and surveillance officers - are advanced trained and "will use whatever speed they deem to be safe".

All response officers can travel 20mph above the speed limit meaning emergency vehicles will be restricted to 40mph in 20mph zones rather than the current 50mph.

ACC Travis added: “If we can stop 10 fatalities a year in Wales then that seems to be a really positive initiative.

“Decisions politically is not something I will comment on as a police officer.”

In response to the leaked email shadow minister for transport Natasha Asghar said: “Labour claim that this policy is to save lives. But with the Police admitting it will impact response times and no work carried out to measure the affect blue light services – contrary to saving lives, I fear that lives will actually be lost."

South Wales Police are set to rollout a campaign labelled ‘Just A Minute’ aimed at advising people on reducing their speed.

South Wales Fire and Rescue staff will offer speeding motorists the opportunity to watch an educational video about the benefits of driving at a slower speed.

Supt Leanne Brustad of Gwent Police said: “Engagement, education, and enforcement plays a huge part in the rollout.

“We will continue to work closely with our partners to educate drivers as much as possible as the new speed limit comes into force and help deliver all of the benefits of this policy.”