Its bosses have urged people to think carefully before dialing 999 for help from its specially trained teams amidst a sustained rise in the volume of calls.
Chief operating officer Paul Liversidge said: “Calls to 999 have reached some of the highest levels on record over the past three weeks, in particular over weekends and on Mondays.
“Of those calls, a greater proportion of them are currently for people who are more seriously ill, who need our services quickly.
"However, reaching those in critical conditions is more challenging right now because we are also seeing a greater number of calls from people who could have been dealt with by a non-emergency service.”
He urged callers to 111 not to redial 999, which should only be used for life-threatening emergencies, with a wait of around 30 minutes for the non-emergency service.
The additional infection prevention control procedures - including daily vehicle deep cleaning and new PPE after each patient - limits the availability of resources to respond, with ambulances only being sent to those most in need and help given over the phone people directed to other services when safe to do so.
Paul added: “We are seeing the impacts of lockdown easing and good weather.
"We’ve had more calls for people injured on the roads or as a result of intoxication and people affected by the heat after not taking the necessary precautions.
"We are using additional third-party resources to increase road capacity and we continue to support our staff, who are understandably fatigued and under pressure.”
He added: “We understand how frustrating it can be to wait for help from our call handling teams or from ambulance crews but please be kind to our staff.
"When we’re under pressure and the number of calls into our service increase, it can take us longer than we would like to reach some patients.
"It’s not their fault if you experience a delay, they’re doing their absolute best.”
People are advised to use 111.nhs.uk, to call their GP or visit their pharmacy and call 119 or Covid tests or track and trace queries.