Response times of the Wales Ambulance Service, published today show that, of red calls, only 51 per cent of calls across Wales were reached within the target of eight minutes.
In Powys the figure is just 43 per cent, a further deterioration on previous months and significantly behind the 65.3 per cent of calls in Cardiff.
The release of figures comes amid calls for Shropshire to have its own ambulance service separate from the West Midlands Ambulance Service because of response times.
Ambulance bosses say staff absence and handover times to hospital A&E departments were partly responsible for the ambulance times.
Responding to the Welsh figures, Welsh Liberal Democrats leader and Mid & West Wales Senedd Member Jane Dodds said: “These figures are a tragedy. Targets aren’t even close to being met and ambulance response times have gotten worse. While we all understand the severe pressure the pandemic has placed on NHS, these problems are not new.
"What really stands out is the huge variance in performance across Wales. Here in Powys, we have some of the worst response times in the country. We absolutely cannot continue with a postcode lottery when it comes to life saving services and rural regions cannot continue to be neglected.
“If we are to reduce pressures on our ambulance services and A&Es, we must invest more in community healthcare and GPs. If people could get a GP appointment in reasonable time there would be far less pressure on emergency services. For too many people in Mid Wales this just isn’t happening and rural Wales continues to suffer from a shortage of GPs.
“We also need action on social care, both to prevent high numbers entering emergency departments and to ensure people have safe environments to be discharged to following any emergency treatment."
Lee Brooks, Director of Operations at the Welsh Ambulance Service, said: “December 2021 was a very challenging month for a number of reasons. As the month unfolded, we moved ever closer to a peak in Omicron variant cases.
“Staff absence peaked on New Year’s Eve with over 360 operational staff unable to be at work due to Covid reasons.
“The combination of challenges across health and social care led to some very long waits for patients to move from an ambulance into emergency departments across the country.
“December reached a new high for total number of hours lost beyond the ideal 15-minute handover time - over 18,600 hours - which meant that patients in need of an ambulance waited longer.
“Capacity provided by partners including St John Ambulance Cymru and the military is continuing to help us attend to patients as quickly as we can.
“Behind these statistics are real people, hard-working staff who are doing all they can to deliver the best possible service to people in Wales in very difficult circumstances, and we’re hugely grateful for their commitment and understanding.
“The public can help us by only calling 999 in a serious or life-threatening emergency – for everything else, the NHS 111 Wales symptom checkers are an excellent place to start if you’re ill or injured and unsure where to turn, as well as your local pharmacy, minor injuries unit and GP.”
At the end of December the Welsh Government announced more than £34 million of extra funding for the Welsh Ambulance Service to tackle winter pressures on the NHS.
Health Minister Eluned Morgan said the Government was determined to support NHS staff as they entered the busiest period of the year.
She said the £34m investment would see more ambulance staff on the frontline, more capacity for patient transport services, and additional support for mental health patients.