Welsh Ambulance Service declare 'critical incident'
A critical incident has been declared by the Welsh Ambulance Service due to high demand, particularly in south east Wales.
The service is asking the public to call 999 only for serious emergencies.
It said some patients may wait longer for help, while others could be advised to make other arrangements if the call is non life-threatening.
Lee Brooks, the trust's director of operations, said actions were under way to deal with demand.
Mr Brooks said: "We really need the public to work with us on this.
"If your call is less urgent, you may wait longer for help, or be asked to make an alternative arrangement, including making your own way to hospital if necessary.
"We're hopeful that the actions we've put in place will start to take effect in the next couple of hours, but until then, help us help you and only call us if it's a genuine emergency."
BBC Wales understands the last time the ambulance service in Wales reached this alert level was in September last year, although it was described as a "significant incident" rather than a critical one.
Ten ambulances are reported to have been waiting outside the new Grange hospital, near Cwmbran, and seven outside Prince Charles Hospital in Merthyr Tydfil.
An incident centre has reportedly been set up at the Welsh Ambulance Service's headquarters in Cwmbran to coordinate efforts to address the situation.
The service are advising that the public can visit the NHS 111 Wales website for health advice or to consult a GP, pharmacist, dentist or optician.