South Western Ambulance Service has declared a critical incident following a surge in emergency calls over the Bank Holiday weekend.
The service has warned that some patients may wait longer for an ambulance while others could be advised to access alternative services if their call is not life-threatening.
The public has been urged only to call 999 in a genuine and life threatening emergency.
SWASFT has dealt with almost 300 additional emergency incidents a day since the government eased lockdown restrictions to allow the reopening of outdoor hospitality and retail on 12 April.
It responded to an average of 2,913 incidents a day last week, compared with 2,816 incidents a day between 12 April and 16 May, and 2,627 incidents a day before any of those changes took effect.