Police chiefs have warned Mark Drakeford's plan to impose a travel ban on English visitors to Wales from coronavirus hotspots is 'unenforceable'.
The Welsh First Minister announced yesterday he intends to prohibit entry to people from areas with high levels of Covid-19 if Boris Johnson fails to impose UK-wide travel restrictions.
But the Police Federation of England and Wales said 'policing in Wales is already over-stretched due to the pandemic' and the new measures would add 'yet another level of complexity to policing'.
The proposals have sparked a furious political backlash with Tory MPs labelling the move 'heavy handed and stupid' as they also accused Mr Drakeford of being 'guilty of small man syndrome'.
Meanwhile, Commons Leader Jacob Rees-Mogg said 'putting a border between England and Wales is unconstitutional' and warned it would put the police in an 'invidious position'.
Mr Drakeford defended his proposals this morning as he said police could use automatic number plate recognition (ANPR) technology to catch visitors from banned areas of the UK.
He also said holiday providers in Wales should not accept bookings from people in hotspot areas of the UK as he warned existing getaway plans 'will no longer be able to be honoured'.
It came as Nicola Sturgeon backed Mr Drakeford's call for nationwide travel restrictions on high incidence areas as she said she would not rule out imposing a Wales-style ban on visitors.
Welsh First Minister Mark Drakeford (pictured in Cardiff in May) said people from coronavirus hotspots in the UK would be hit with fines if they travel to Wales
Tory MPs have accused Mr Drakeford of being 'guilty of small man syndrome'. The Welsh First Minister is pictured with Boris Johnson in July last year
Nicola Sturgeon has backed Mr Drakeford's calls for Mr Johnson to introduce UK-wide travel restrictions on hotspot areas
Welsh First Minister Mark Drakeford yesterday announced an extraordinary bid to ban people from coronavirus hotspots in England entering the country.
In Wales, health protection legislation - a devolved power - falls under the Public Health (Control of Disease) Act 1984.
It was updated in 2010 to give public authorities 'more comprehensive powers and duties to prevent and control risks to human health from infection or contamination'.
In its basic form, the act allows Welsh ministers to make laws 'for the purpose of preventing, protecting against, controlling or providing a public health response to the incidence or spread of infection or contamination in Wales'.
The laws that can be put forward include 'restrictions or requirements on or in relation to persons, things or premises in the event of, or in response to, a threat to public health'.
While the act does not specifically mention limitations on movements, the travel ban will likely be made law using the powers it grants.
However, the unprecedented nature of Mr Drakeford's proposals - and the prospect of ANPR being used to catch rule-breakers - could result in a legal challenge.
Mr Drakeford told the Welsh Parliament yesterday that he had asked for work on the travel ban to be brought forward after Mr Johnson failed to reply to two letters requesting he introduce the measure across the UK.
The Welsh Government's plans will bring people elsewhere in the UK in line with measures currently in place in the 17 areas of Wales under local lockdown restrictions.
Under those rules, people must not enter or leave an affected area without a reasonable excuse such as work or education.
But currently, people living in Covid-19 hotspots elsewhere in the UK are free to enter areas of Wales not under restrictions where levels of the virus are low.
The ban is likely to apply to people living in Tier Two and Tier Three areas of England and is designed to prevent them from travelling to tourist destinations such as the far west and south west of Wales, which have low levels of coronavirus.
It will also affect those living in areas of Scotland and Northern Ireland with a high prevalence of Covid-19.
Those who ignore the restrictions will be breaking the law and could face fixed penalty notices starting at £50.
But Mark Bleasdale, Police Federation of England and Wales' Welsh Lead, said: 'On the face of it, this is unenforceable because of the difficulty of identifying where people are coming from and where they are going to.
'There will also be plenty of individuals travelling legitimately from areas which are not high risk, and this will